4,056 research outputs found
Information entropy of classical versus explosive percolation
We study the Shannon entropy of the cluster size distribution in classical as
well as explosive percolation, in order to estimate the uncertainty in the
sizes of randomly chosen clusters. At the critical point the cluster size
distribution is a power-law, i.e. there are clusters of all sizes, so one
expects the information entropy to attain a maximum. As expected, our results
show that the entropy attains a maximum at this point for classical
percolation. Surprisingly, for explosive percolation the maximum entropy does
not match the critical point. Moreover, we show that it is possible determine
the critical point without using the conventional order parameter, just
analysing the entropy's derivatives.Comment: 6 pages, 6 figure
Temporal genotypic diversity of Schizaphis graminum (Rondani 1852) (Hemiptera: Aphididae) in a black oats (Avena strigosa) field.
Heterogeneity in the Second Internal Transcribed Spacer (ITS2) of rDNA in the genetically distinct Metopolophium dirhodum isofemale lineages (Hemiptera: Aphididae).
Manual de interpretação de trilhas: explorando os conceitos de ecologia e conservação de floresta na Reserva do Caju.
bitstream/CPATC-2010/20867/1/doc-149.pd
Genetic parameter and correlation estimates of processing traits in half-sib progenies of tropical-adapted carrot germplasm.
Setenta e quatro progênies meio-irmãs derivadas de 'Alvoradas' foram avaliadas durante o verão de 2005 no Distrito Federal (DF), em blocos casualizados com três repetições
TWO-STROKE ENGINE BEHAVIOR (SMALL CHAINSAW) OPERATING WITH NON-COMMERCIAL FUEL BLENDS AND DIVERSE LUBRICATION
The paper presents results for experimental tests in a two-stroke internal combustions engine operating on commercial fuel (gasoline and ethanol blends), with different proportions in mineral oil for lubrication purposes. Appropriate instrumentation was used to carry out the measurement of the quantities of interest, namely fuel consumption (g/s), angular velocity (rpm) and emissions (CO2 and NOx). The methodology was based on regulations from INMETRO (motor vehicles energy conversion efficiency) and ABNT (testing of internal combustion engines). Results obtained are analyzed and discussed for the fuel consumption versus angular velocity (g/s x rpm) for each combination fuel blend and lubricating oil (quantities). Main findings are that fuel consumption increases non linearly as angular velocity increases and as lubrication lowers, while emissions decreases as angular velocity increases. Lowest fuel consumption and emissions occurred, respectively, for A25/L1:25 and A25/L1:50 (commercial fuel and standard lubrication)
Estimativas de parâmetros genéticos visando a seleção para resistência à queima-das-folhas em populações de cenoura do grupo BrasÃlia.
bitstream/CNPH-2009/34418/1/bpd_36.pd
Information representation in Displaced Archives: a meta-synthesis
The phenomenon of displaced archives emerges in the scientific literature as a kind of wicked problem. In addition to the conceptual diversity associated with this phenomenon present in the scientific literature from various fields (e.g., removed archives, migrated archives, seized archives, alienated archives, captured archives, diasporic archives, expatriated/repatriated archives, estray archival, disputed archival claims, replevin, etc.), there is a tendency in the scientific community to adopt the concept of displaced archives as a possible hypernym. The most recent definition of displaced archive is found in the report issued by the International Council on Archives through the Expert Group on Shared Archival Heritage, understood as "archives removed from the place of their creation, where the ownership of the archives is disputed by two or more parties" (Lowry 2020, 5). Nevertheless, one of the problems that makes this phenomenon a particular case is whether we can identify archives that are in the condition of displaced without there necessarily having to be claimant party(ies) for that purpose.
Although the most recurrent focus in addressing this phenomenon has been around the problems of restitution, repatriation, return or relocation, the identification and, more incisively, the representation of these documentary sets have remained obscured in scientific discourse. According to Winn (2015), one of the limiting factors in the identification of displaced archives consists, among others, in the inexistence of information access tools. For Lowry, "the catalogue is the key" (2017a, 8), not only as an instrument of access to information where the processes of organization and description are materialized with a view to its retrieval and access, but also as a mechanism of information representation that derives from the powers of archival mediation.
Studies on information representation suggest that, in the postmodern archival stream, it is not possible to ensure neutrality or impartiality in the representation of the content and structure of a fonds (MacNeil 2012) in finding aids. Such archival descriptions are supported by interpretative approaches that depend on the description and access policies adopted by custodians, which are not unrelated to the political, historical, socio-cultural, and institutional contexts of the environment where they were produced.
Considering that the finding aids can be genologically diverse (e.g., catalogues, inventories, guides, scripts, directories, indexes and databases), it is considered more productive to focus on the representation of archival information, from the perspective of how a "fluid, evolving, and socially constructed practice" (Yakel 2003, 2) is constituted as "the core of archival description produced to facilitate access to archival materials in the background of their creation and custodial history" (Zhang 2012, 49).
Considering that some of the studies on archival information representation have been problematized with greater incidence, although incipient, in Knowledge Organization and Information Science (Barros and Sousa 2020; Aguiar and Kobashi 2013; Tognoli 2013; Vital, Medeiros, and Brascher 2017; Corujo and Freitas 2021; Tognoli and Guimarães 2011; 2012; Troitiño Rodriguez 2018; Hjørland 2002), these studies have largely confined themselves to material and technical processes, physical (u. g., arrangement) and intellectual (u. g., classification and description), of concepts that conform to the bureaucratic dimension of the producers and/or custodial entities. In what concerns the displaced archives, the phenomenon itself challenges the core concepts of Archival Science, especially how these disputed documentary sets are represented from the point of view of provenance, integrity, organicity and how these representations are (re)constructed or destroyed in the process of archival mediation.
Based on these aspects, and given the scarcity of studies on this topic, this article focuses on how the representation of information about archives removed from their original social and territorial contexts has been addressed in the scientific literature. Thus, we intend to conduct a survey of scientific literature that informs about the trajectory of the information representation process from the removal process to the claim by the dispossessed communities that can be theoretically relevant to the scope of Knowledge Organization. Thus, based on the above, it justifies performing a synthesis of knowledge from scientific literature called meta-synthesis (Sandelowski and Barroso 2010; Grant and Booth 2009; Finfgeld-Connett 2018). Thus, this article is structured as follows: section 2.0 formulates the starting question and research objectives; section 3.0 outlines the methodological assumptions for this type of qualitative literature synthesis; section 4.0 presents the results of the empirical investigation; section 5.0 makes concluding remarks around limitations and implications, as well as future lines of research.info:eu-repo/semantics/submittedVersio
Below the Nation State: Power Asymmetry and Jurisdictional Boundaries around the Archives of Madeira Archipelago
The main purpose of this chapter is to describe a case study developed in a sub-national context between the Autonomous Region of Madeira and the National Archive ‘Torre do Tombo’ (ANTT). Our analysis will
focus theoretically on the etiologies of dispossession and empirically on a case study. Thus, the main questions that will lead this case study are: ‘Why were the Madeiran fonds taken in the past to or by ANTT?’ and ‘How were these Madeiran fonds represented in finding aids provided by ANTT and the RAM?’. Finally, based on nissological critiques,13 we will define and contextualise the notion of sub-national displaced archives as an underresearched subset of disputed archival claims, in order to reveal some particular aspects of this phenomenon.info:eu-repo/semantics/publishedVersio
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