1,786 research outputs found
Algorithm for Adapting Cases Represented in a Tractable Description Logic
Case-based reasoning (CBR) based on description logics (DLs) has gained a lot
of attention lately. Adaptation is a basic task in the CBR inference that can
be modeled as the knowledge base revision problem and solved in propositional
logic. However, in DLs, it is still a challenge problem since existing revision
operators only work well for strictly restricted DLs of the \emph{DL-Lite}
family, and it is difficult to design a revision algorithm which is
syntax-independent and fine-grained. In this paper, we present a new method for
adaptation based on the DL . Following the idea of
adaptation as revision, we firstly extend the logical basis for describing
cases from propositional logic to the DL , and present a
formalism for adaptation based on . Then we present an
adaptation algorithm for this formalism and demonstrate that our algorithm is
syntax-independent and fine-grained. Our work provides a logical basis for
adaptation in CBR systems where cases and domain knowledge are described by the
tractable DL .Comment: 21 pages. ICCBR 201
Ages on weathered Plio-Pleistocene tephra sequences, western North Island, New Zealand
Using the zircon fission-track method, we have obtained five ages on members of two strongly-weathered silicic, Pliocene-Pleistocene tephra sequences, the Kauroa and Hamilton Ash formations, in western North Island, New Zealand. These are the first numerical ages to be obtained directly on these deposits. Of the Kauroa Ash sequence, member K1 (basal unit) was dated at 2.24 ± 0.29 Ma, confirming a previous age of c. 2.25 Ma obtained (via tephrochronology)from K/Ar ages on associated basalt lava. Members K2 and K3 gave indistinguishable ages between 1.68 ± 0.12 and 1.43 ± 0.17 Ma. Member K12, a correlative of Oparau Tephra and probably also Ongatiti Ignimbrite, was dated at 1.28 ± 0.11 Ma, consistent with an age of 1.23 ± 0.02 Ma obtained by various methods on Ongatiti Ignimbrite. Palaeomagnetic measurements indicated that members K13 to K15 (top unit, Waiterimu Ash) are aged between c. 1.2 Ma and 0.78 Ma. Possible sources of the Kauroa Ash Formation include younger volcanic centres in the southern Coromandel Volcanic Zone or older volcanic centres in the Taupo Volcanic Zone, or both. Of the Hamilton Ash sequence, the basal member Ohinewai Ash (HI) was dated at 0.38 ± 0.04 Ma. This age matches those obtained by various methods on Rangitawa Tephra of 0.34-0.35 Ma, supporting correlation with this Whakamaru-caldera derived deposit. The origin of the other Hamilton Ash beds is unknown but various younger volcanic centres in the Taupo Volcanic Zone are possible sources. The topmost member, Tikotiko Ash (H6-H7), is estimated to be aged between c. 0.18 and 0.08 Ma. Various silicic pyroclastic deposits documented in North Island and in marine cores may be co-eval with members of the Kauroa Ash and Hamilton Ash sequences on the basis of their age
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Exploring the health service response to women experiencing domestic violence in Wakefield: adopting a discursive approach
This report presents the findings of a research study exploring the health service response to domestic violence
within Wakefield. Recent international, national and local research has identified domestic violence as a serious
health care issue resulting in a wide range of long and short term health implications for women1 (Butler, 1995:
Stark and Flitcraft, 1995, 1996: Campbell, 2002). The research highlights the changing face of domestic violence
considering the implications of the recent reframing of domestic violence from a social care issue into an
integrated health and social care issue (Glendinning, 2003). Explored is the impact of such changes for health
policy makers, health professionals and women who having experienced domestic violence then access health
care services in the District.Eastern Wakefield Primary Care Trus
ColNet: Embedding the Semantics of Web Tables for Column Type Prediction
Automatically annotating column types with knowledge base(KB) concepts is a critical task to gain a basic understandingof web tables. Current methods rely on either table metadatalike column name or entity correspondences of cells in theKB, and may fail to deal with growing web tables with in-complete meta information. In this paper we propose a neu-ral network based column type annotation framework namedColNetwhich is able to integrate KB reasoning and lookupwith machine learning and can automatically train Convolu-tional Neural Networks for prediction. The prediction modelnot only considers the contextual semantics within a cell us-ing word representation, but also embeds the semantics of acolumn by learning locality features from multiple cells. Themethod is evaluated with DBPedia and two different web ta-ble datasets, T2Dv2 from the general Web and Limaye fromWikipedia pages, and achieves higher performance than thestate-of-the-art approaches
Combinatorial Games with a Pass: A dynamical systems approach
By treating combinatorial games as dynamical systems, we are able to address
a longstanding open question in combinatorial game theory, namely, how the
introduction of a "pass" move into a game affects its behavior. We consider two
well known combinatorial games, 3-pile Nim and 3-row Chomp. In the case of Nim,
we observe that the introduction of the pass dramatically alters the game's
underlying structure, rendering it considerably more complex, while for Chomp,
the pass move is found to have relatively minimal impact. We show how these
results can be understood by recasting these games as dynamical systems
describable by dynamical recursion relations. From these recursion relations we
are able to identify underlying structural connections between these "games
with passes" and a recently introduced class of "generic (perturbed) games."
This connection, together with a (non-rigorous) numerical stability analysis,
allows one to understand and predict the effect of a pass on a game.Comment: 39 pages, 13 figures, published versio
The Increasing Role of Percutaneous Transluminal Angioplasty in the Primary Management of Critical Limb Ischaemia
AbstractObjective: to review the current role and results of angioplasty in the management of critical limb ischaemia (CLI) in a single institution.Methods: data on 526 patients with 608 ischaemic limbs, treated between January 1994 and December 1999 was collected prospectively and analysed retrospectively. Patients were divided into 3 groups according to the date of presentation: group 1 (1994–95), group 2 (1996–97) and group 3 (1998–99). The groups were comparable in terms of demographics, mode of presentation and level of disease.Results: Revascularisation was attempted in 87%, 81% and 91% for groups 1, 2 and 3 respectively (NS). Primary percutaneous transluminal angioplasty (PTA) rates increased from 44% (1994–95) to 69% (1998–99) (p < 0.001), and surgical revascularisation rates decreased correspondingly (p<0.01). Overall cumulative patient survival and limb salvage rates were 82% and 89% for 1 year and 45% and 87% for 5 years, respectively. No statistically significant difference existed between the three groups regarding patient survival, limb salvage rates and mean hospital stay (19, 12 and 12 days, respectively).Conclusion: PTA is increasingly replacing bypass surgery in the treatment of CLI, without compromising patient survival or limb salvage rates
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