22,962 research outputs found
Extracting scaling laws from numerical dynamo models
Earth's magnetic field is generated by processes in the electrically
conducting, liquid outer core, subsumed under the term `geodynamo'. In the last
decades, great effort has been put into the numerical simulation of core
dynamics following from the magnetohydrodynamic (MHD) equations. However, the
numerical simulations are far from Earth's core in terms of several control
parameters. Different scaling analyses found simple scaling laws for quantities
like heat transport, flow velocity, magnetic field strength and magnetic
dissipation time.
We use an extensive dataset of 116 numerical dynamo models compiled by
Christensen and co-workers to analyse these scalings from a rigorous model
selection point of view. Our method of choice is leave-one-out cross-validation
which rates models according to their predictive abilities. In contrast to
earlier results, we find that diffusive processes are not negligible for the
flow velocity and magnetic field strength in the numerical dynamos. Also the
scaling of the magnetic dissipation time turns out to be more complex than
previously suggested. Assuming that the processes relevant in the numerical
models are the same as in Earth's core, we use this scaling to estimate an
Ohmic dissipation of 3-8 TW for the core. This appears to be consistent with
recent high CMB heat flux scenarios.Comment: 21 pages, 11 figure
Developing the egovernment research agenda
This paper presents an exploratory research project to determine the needs for future eGovernment research. The project aimed particularly at getting relevant stakeholder views as a contrast to the received academic wisdom or political rhetoric. This paper outlines the need for such fieldwork and discusses the methodology adopted to elicit the stakeholdersâ views without influencing the debate. The VIEGO workshops have shown that an eGovernment research agenda will require a multi-disciplinary approach involving a combination of social, technological and organisational issues. The primary concerns of stakeholders are not to develop more novel IT but to acquire the means to cope with constant change, coordinate development and extend participation.UKâs Engineering Physical Sciences Research
Council (EPSRC)-(grant EP/ D043840/1
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Electronic transformation of government in the U.K.: a research agenda
This paper presents the findings of an exploratory research project into future
e-Government (electronic Government) initiatives. The Virtual Institute for
Electronic Government Research (VIEGO) project aimed at identifying and
further developing the research agenda of e-Government based on a solid
practical ground. As such, the paper offers a novel methodology in identifying
the road map for future e-Government initiatives based on a series of
workshops organised around the U.K. hosting a mixture of stakeholders
involving both academics and parishioners. The analysis of the VIEGO
workshops depicted that an e-Government research agenda involves a
combination of social, technological and organisational issues at both
governmental and individual citizen level, ultimately driven by empirical
case-based experience and active participation in e-Government processes.
Unlike other propositions for the future of e-Government offered in the e-
Government literature, raised research questions not only originated from an
analysis of e-Government literature but also on the outcome of brainstorming,
reflections and contemplations throughout the duration of the project
Principal component analysis - an efficient tool for variable stars diagnostics
We present two diagnostic methods based on ideas of Principal Component
Analysis and demonstrate their efficiency for sophisticated processing of
multicolour photometric observations of variable objects.Comment: 8 pages, 4 figures. Published alread
Community College Culture and Faculty of Color
This investigation examines and explains the ways in which community college faculty of color construct their understandings of institutional culture. We investigate four community colleges in California through interviews with 31 full-time faculty of color. This faculty group expresses identity conflicts between their professional roles and their cultural identities. Their understandings of their institutions suggest that the culture of the community college is more complex and multi-faceted than that portrayed in the scholarly literature, which often portrays the institution as homogeneous and the faculty body as uniform. © The Author(s) 2013
The Divided Self: The Double Consciousness of Faculty of Color in Community Colleges
Through qualitative field methods research addressing faculty of color in four California community colleges, this investigation examines and explains faculty experiences and professional sense making. By combining critical race theory with social identity theory, our perspective underlines the potential social and ethnic identity conflicts inherent in the daily lives of faculty of color. The professional and social identities of faculty of color are not necessarily compatible, leading to a condition of "double consciousness," or what we refer to as "the divided self." © The Author(s) 2013
âDangerous Workâ: Improving Conditions for Faculty of Color in the Community College
This qualitative investigation of the experiences of faculty of color at community colleges identifies current conditions for this population and suggests potentials for ameliorating conditions that inhibit their job satisfaction. We argue that the current conditions for faculty of color, based upon their expressed experiences at the community colleges, are deleterious to their professional performance, to their positive self-image, and to their contributions to their institutions. Alterations to these current conditions are unlikely without systemic institutional change. Indeed, without improvement to these conditions, the job satisfaction of faculty of color is not likely to change
Monopolizing force?: police legitimacy and public attitudes towards the acceptability of violence
Why do people believe that violence is acceptable? In this paper we study peopleâs normative beliefs about the acceptability of violence to achieve social control (as a substitute for the police, for self-protection and the resolution of disputes) and social change (through violent protests and acts to achieve political goals). Addressing attitudes towards violence among young men from various ethnic minority communities in London, we find that procedural justice is strongly correlated with police legitimacy, and that positive judgments about police legitimacy are associated with more negative views about the use of violence. We conclude with the idea that police legitimacy has an additional, hitherto unrecognized, empirical property â by constituting the belief that the police monopolise rightful force in society, legitimacy has a âcrowding outâ effect on positive views of private violence
The Life and Works of Rashīd al-Dīn: Jewish Vizier in the Mongol Ilkhanid Court
In this paper I wish to illuminate the life of historian and author RashÄ«d al-DÄ«n Fadhl-allÄh HamadÄnÄ«, a Jewish vizier during the rule of the Mongol Ilkhans in Iran. By gaining a better grasp of the manâs personal biography, I hope to give insight into his lifeâs most notable work: the Jami al-Tawarikh, or the Compendium of Chronicles (ca. 1305-06), the first comprehensive world history of its kind ever produced and Rashid al-Dinâs greatest contribution to Ilkhanid literary space. It serves as our best source for understanding the Pax Mongolica of the thirteenth and fourteenth centuries that embraced Iran, and the Mongol understanding of their world and their place in history at that time. Its styles and motifs reflect the multicultural fusion of the Mongol dynasty, where eastern influences blended with a revived Persian aesthetic
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