721 research outputs found
Existence of Monetary Steady States in a Matching Model: Indivisible Money
Existence of a monetary steady state is established for a random matching model with divisible goods, indivisible money, and take-it-or-leave-it offers by consumers. There is no restriction on individual money holdings. The background environment is that in papers by Shi and by Trejos and Wright. The monetary steady state shown to exist has nice properties: the value function, defined on money holdings, is increasing and strictly concave, and the measure over money holdings has full support.
Fusions of Description Logics and Abstract Description Systems
Fusions are a simple way of combining logics. For normal modal logics,
fusions have been investigated in detail. In particular, it is known that,
under certain conditions, decidability transfers from the component logics to
their fusion. Though description logics are closely related to modal logics,
they are not necessarily normal. In addition, ABox reasoning in description
logics is not covered by the results from modal logics. In this paper, we
extend the decidability transfer results from normal modal logics to a large
class of description logics. To cover different description logics in a uniform
way, we introduce abstract description systems, which can be seen as a common
generalization of description and modal logics, and show the transfer results
in this general setting
Computing FO-Rewritings in EL in Practice: from Atomic to Conjunctive Queries
A prominent approach to implementing ontology-mediated queries (OMQs) is to
rewrite into a first-order query, which is then executed using a conventional
SQL database system. We consider the case where the ontology is formulated in
the description logic EL and the actual query is a conjunctive query and show
that rewritings of such OMQs can be efficiently computed in practice, in a
sound and complete way. Our approach combines a reduction with a decomposed
backwards chaining algorithm for OMQs that are based on the simpler atomic
queries, also illuminating the relationship between first-order rewritings of
OMQs based on conjunctive and on atomic queries. Experiments with real-world
ontologies show promising results
Insulin Glargine in the Intensive Care Unit: A Model-Based Clinical Trial Design
Online 4 Oct 2012Introduction: Current succesful AGC (Accurate Glycemic Control) protocols require extra clinical effort and are impractical in less acute wards where patients are still susceptible to stress-induced hyperglycemia. Long-acting insulin Glargine has the potential to be used in a low effort controller. However, potential variability in efficacy and length of action, prevent direct in-hospital use in an AGC framework for less acute wards.
Method: Clinically validated virtual trials based on data from stable ICU patients from the SPRINT cohort who would be transferred to such an approach are used to develop a 24-hour AGC protocol robust to different Glargine potencies (1.0x, 1.5x and 2.0x regular insulin) and initial dose sizes (dose = total insulin over prior 12, 18 and 24 hours). Glycemic control in this period is provided only by varying nutritional inputs. Performance is assessed as %BG in the 4.0-8.0mmol/L band and safety by %BG<4.0mmol/L.
Results: The final protocol consisted of Glargine bolus size equal to insulin over the previous 18 hours. Compared to SPRINT there was a 6.9% - 9.5% absolute decrease in mild hypoglycemia (%BG<4.0mmol/L) and up to a 6.2% increase in %BG between 4.0 and 8.0mmol/L. When the efficacy is known (1.5x assumed) there were reductions of: 27% BG measurements, 59% insulin boluses, 67% nutrition changes, and 6.3% absolute in mild hypoglycemia.
Conclusion: A robust 24-48 clinical trial has been designed to safely investigate the efficacy and kinetics of Glargine as a first step towards developing a Glargine-based protocol for less acute wards. Ensuring robustness to variability in Glargine efficacy significantly affects the performance and safety that can be obtained
A Graphical User Interface for Formal Proofs in Geometry.
International audienceWe present in this paper the design of a graphical user interface to deal with proofs in geometry. The software developed combines three tools: a dynamic geometry software to explore, measure and invent conjectures, an automatic theorem prover to check facts and an interactive proof system (Coq) to mechanically check proofs built interactively by the user
Nominal Unification of Higher Order Expressions with Recursive Let
A sound and complete algorithm for nominal unification of higher-order
expressions with a recursive let is described, and shown to run in
non-deterministic polynomial time. We also explore specializations like nominal
letrec-matching for plain expressions and for DAGs and determine the complexity
of corresponding unification problems.Comment: Pre-proceedings paper presented at the 26th International Symposium
on Logic-Based Program Synthesis and Transformation (LOPSTR 2016), Edinburgh,
Scotland UK, 6-8 September 2016 (arXiv:1608.02534
Effect of the Output of the System in Signal Detection
We analyze the consequences that the choice of the output of the system has
in the efficiency of signal detection. It is shown that the signal and the
signal-to-noise ratio (SNR), used to characterize the phenomenon of stochastic
resonance, strongly depend on the form of the output. In particular, the SNR
may be enhanced for an adequate output.Comment: 4 pages, RevTex, 6 PostScript figure
Get my pizza right: Repairing missing is-a relations in ALC ontologies (extended version)
With the increased use of ontologies in semantically-enabled applications,
the issue of debugging defects in ontologies has become increasingly important.
These defects can lead to wrong or incomplete results for the applications.
Debugging consists of the phases of detection and repairing. In this paper we
focus on the repairing phase of a particular kind of defects, i.e. the missing
relations in the is-a hierarchy. Previous work has dealt with the case of
taxonomies. In this work we extend the scope to deal with ALC ontologies that
can be represented using acyclic terminologies. We present algorithms and
discuss a system
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