56 resultados para Història local
Resumo:
This paper characterizes when a Delone set X in R-n is an ideal crystal in terms of restrictions on the number of its local patches of a given size or on the heterogeneity of their distribution. For a Delone set X, let N-X (T) count the number of translation-inequivalent patches of radius T in X and let M-X (T) be the minimum radius such that every closed ball of radius M-X(T) contains the center of a patch of every one of these kinds. We show that for each of these functions there is a gap in the spectrum of possible growth rates between being bounded and having linear growth, and that having sufficiently slow linear growth is equivalent to X being an ideal crystal. Explicitly, for N-X (T), if R is the covering radius of X then either N-X (T) is bounded or N-X (T) greater than or equal to T/2R for all T > 0. The constant 1/2R in this bound is best possible in all dimensions. For M-X(T), either M-X(T) is bounded or M-X(T) greater than or equal to T/3 for all T > 0. Examples show that the constant 1/3 in this bound cannot be replaced by any number exceeding 1/2. We also show that every aperiodic Delone set X has M-X(T) greater than or equal to c(n)T for all T > 0, for a certain constant c(n) which depends on the dimension n of X and is > 1/3 when n > 1.
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We present a novel maximum-likelihood-based algorithm for estimating the distribution of alignment scores from the scores of unrelated sequences in a database search. Using a new method for measuring the accuracy of p-values, we show that our maximum-likelihood-based algorithm is more accurate than existing regression-based and lookup table methods. We explore a more sophisticated way of modeling and estimating the score distributions (using a two-component mixture model and expectation maximization), but conclude that this does not improve significantly over simply ignoring scores with small E-values during estimation. Finally, we measure the classification accuracy of p-values estimated in different ways and observe that inaccurate p-values can, somewhat paradoxically, lead to higher classification accuracy. We explain this paradox and argue that statistical accuracy, not classification accuracy, should be the primary criterion in comparisons of similarity search methods that return p-values that adjust for target sequence length.
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What interactions are sufficient to simulate arbitrary quantum dynamics in a composite quantum system? We provide an efficient algorithm to simulate any desired two-body Hamiltonian evolution using any fixed two-body entangling n-qubit Hamiltonian and local unitary operations. It follows that universal quantum computation can be performed using any entangling interaction and local unitary operations.
Resumo:
Government policy change to self detennination over the past two decades has gradually given rise to various structures of Indigenous self government across Australia. Indigenous Local Government Authorities (LGAs) are the governing structure which receive the greatest devolution of State authority, especially those found in Queensland and the Northern Territory. Their statutory basis has developed over a relatively short period of time and is still very much evolving. This paper explores what opportunities exist for Indigenous LGAs to adopt statutory planning mechanisms.
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Coral reefs are one of the most diverse habitats in the world [1], yet our understanding of the processes affecting their biodiversity is limited [1-3]. At the local scale, cleaner fish are thought to have a disproportionate effect, in relation to their abundance and size, on the activity of many other fish species, but confirmation of this species' effect on local fish diversity has proved elusive. The cleaner fish Labroides dimidiatus has major effects on fish activity patterns [4] and may indirectly affect fish demography through the removal of large numbers of parasites [5, 6]. Here we show that small reefs where L. dimidiatus had been experimentally excluded for 18 months had half the species diversity of fish and one-fourth the abundance of individuals. Only fish that move among reefs, however, were affected. These fish include large species that themselves can affect other reef organisms [2, 7]. In contrast, the distribution of resident fish was not affected by cleaner fish. Thus, many fish appear to choose reefs based on the presence of cleaner fish. Our findings indicate that a single small [8] and not very abundant [9] fish has a strong influence on the movement patterns, habitat choice, activity, and local diversity and abundance of a wide variety of reef fish species.
Resumo:
In the paper we present two continuous selection theorems in hyperconvex metric spaces and apply these to study xed point and coincidence point problems as well as variational inequality problems in hyperconvex metric spaces.
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The Queensland Government is increasingly using participatory planning as a means to improve infrastructure and service delivery to Indigenous settlements. In addition to technical and economic goals, participatory planning practice seeks also to achieve social development goals, including empowerment, capacity building, community control and ownership. This article presents the findings of an evaluation of one such planning project, conducted at Old Mapoon in 1995. Despite various efforts to follow participatory processes, the plan had mixed success in achieving social development goals. This suggests some misunderstandings between the practice of participatory planning and the workings of local governance. It also presents some opportunities for participatory planning methods to be integrated with more inclusive forms of governance.
Resumo:
As a result of the local autonomy program that commenced in Indonesia in Jan 2001, there is a concern regarding the applicability of the formalized model of security & the possibility of that being replaced by a local community-based security model. This rather informal security model is then promoted to be the only form of security used between societies & the nation. However, this model does not solve the problem because of widespread corruption, collusion, & nepotism, & the many limitations of the Indonesian National Police (Polri), a police department that has a mediocre & generalized level of service. In relation to autonomy, the effort of empowering the police units from the regional police down will bridge the gap between the people's ability to protect themselves & the limitations of those that are sworn to uphold the law. 17 References. Adapted from the source document.
Resumo:
Pippa Norris provides a schematic account of the evolution of campaigning through premodern, modern and postmodern stages. In particular she points to an emerging postmodern phase of electioneering characterized by a renewed emphasis upon direct forms of engagement which resonate with an earlier period in which campaigns were locally fought and largely dependent upon the canvassing efforts of party workers and volunteers. Norris's analysis offers a useful prism with which to view recent developments in electioneering in Australia. In the past several elections the rival Labor and Liberal parties have attempted to achieve a synergy between their centrally conducted and constituency-level campaigns by ensuring that their national campaigns are locally relevant and address local concerns. Their efforts to 'localize the national' meld the use of sophisticated software with elements of a traditional 'meet and greet' politics and suggest that local campaigning may now have a new shape and importance.