616 research outputs found
Models of Consensus for Multiple Agent Systems
Models of consensus are used to manage multiple agent systems in order to
choose between different recommendations provided by the system. It is assumed
that there is a central agent that solicits recommendations or plans from other
agents. That agent the n determines the consensus of the other agents, and
chooses the resultant consensus recommendation or plan. Voting schemes such as
this have been used in a variety of domains, including air traffic control.
This paper uses an analytic model to study the use of consensus in multiple
agent systems. The binomial model is used to study the probability that the
consensus judgment is correct or incorrect. That basic model is extended to
account for both different levels of agent competence and unequal prior odds.
The analysis of that model is critical in the investigation of multiple agent
systems, since the model leads us to conclude that in some cases consensus
judgment is not appropriate. In addition, the results allow us to determine how
many agents should be used to develop consensus decisions, which agents should
be used to develop consensus decisions and under which conditions the consensus
model should be used.Comment: Appears in Proceedings of the Tenth Conference on Uncertainty in
Artificial Intelligence (UAI1994
Learning Concise Models from Long Execution Traces
Abstract models of system-level behaviour have applications in design
exploration, analysis, testing and verification. We describe a new algorithm
for automatically extracting useful models, as automata, from execution traces
of a HW/SW system driven by software exercising a use-case of interest. Our
algorithm leverages modern program synthesis techniques to generate predicates
on automaton edges, succinctly describing system behaviour. It employs trace
segmentation to tackle complexity for long traces. We learn concise models
capturing transaction-level, system-wide behaviour--experimentally
demonstrating the approach using traces from a variety of sources, including
the x86 QEMU virtual platform and the Real-Time Linux kernel
Las especies de salvia (Lamiaceae) para Argentina
Salvia es el género más grande de la familia Lamiaceae, con ca. 900 espcies. En Argentina está representado por 23 taxones (20 especies, una subespecie y dos variedades), cuatro de estos taxones son adventicios, el resto nativos y uno de ellos es endémico. Las especies se distribuyen principalmente en el norte del territorio, llegando a las provincias de La Pampa y Mendoza como lÃmite sur de su distribución. Cada uno de los 23 taxones de Salvia presentes en Argentina es descripto e ilustrado y se presenta una clave para su identificación. Se proponen tres nuevos sinónimos, Salvia borjensis nuevo sinónimo de Salvia nervosa, Salvia durifolia nuevo sinónimo de Salvia ovalifolia var. ovalifolia y Salvia alba nuevo sinónimo de Salvia personata, y se designan diez lectotipos para: Salvia approximata, S. arenaria, S. ovalifolia var. villosa, S. pallida, S. procurrens, S. reflexa, S. serrata, S. stachydifolia, S. uliginosa y Salvia sect. Pycnosphace.Salvia is the biggest genus from Lamiceae, with almost 900 species. In Argentina it is represented by 23 taxa (20 species, one subspecies, and two varieties), four of these are adventive taxa, the rest are native, and one of these is endemic. Species are distributed predominantly in the north region of the territory, reaching the provinces of La Pampa and Mendoza as the southern limit of its distribution. Each of the 23 Salvia taxa present in Argentina is described and illustrated, and a key for their identification is presented. Three new synonyms are proposed, Salvia borjensis new synonym of Salvia nervosa, Salvia durifolia new synonym of Salvia ovalifolia var. ovalifolia and Salvia alba new synonym of Salvia personata, and ten lectotypes are designated for: Salvia approximata, S. arenaria, S. ovalifolia var. villosa, S. pallida, S. procurrens, S. reflexa, S. serrata, S. stachydifolia, S. uliginosa, and Salvia sect. Pycnosphace.Fil: O'Leary, Nataly Cristina. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, FÃsicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: Moroni, Pablo Daniel. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, FÃsicas y Naturales. Instituto de Botánica Darwinion; Argentin
Modulations of voice and translations of text : the Victorian background of James Joyce's Ulysses
Points out the philosophical and especially the philological influences which shaped Joyce's writing
Repeatability and validity of the PowerRefractor and the Nidek AR600-A in an adult population with healthy eyes
We assessed the repeatability and validity of the PowerRefractor and the Nidek AR-600A autorefractor. This is the first independent study conducted on adults to evaluate the performance of these instruments in a laboratory setting. Fifty subjects (23 males and 27 females) aged 16 to 61 years (mean, 37 ± 12) participated in the study. The validity of the PowerRefractor and the Nidek autorefractor readings were determined by comparing them to subjective refraction. Measurements of refractive error were obtained from the two instruments on two separate occasions to assess their repeatability. The measured refractive error was converted into a dioptric power matrix for data analysis. No significant difference was found between the measurements obtained with the two instruments and the subjective refraction. The estimate of refractive error given by the two instruments was also found to be repeatable. In addition to measuring the refractive error, the PowerRefractor also offers the facility to measure eye position, pupil size, and dynamics of accommodation. We suggest some improvements to the PowerRefractor measurement technique to standardize its clinical use and to improve accuracy
(2625) Proposal to reject the name Littorella spicata (Plantaginaceae)
Littorella flexuosa Raf., New Fl. 4: 12-13. 1838 [incorrectly given as 1836], nom. rej. prop.Typus: non designatus. Littorella subgenus Xamotris Raf., New Fl. 4: 12. 1838 [incorrectly given as 1836], nom. rej. prop.Lectotypus (designated here): Littorella flexuosa Raf. In accordance to Art. 56.1, we believe that the best course of action would be to reject the name L. flexuosa, along with Littorella subgenus Xamotris, in order to prevent that a considerably dubious name threaten a well-stablished species name, causing a disadvantageous nomenclatural change.Fil: Hassemer, Gustavo. Universidad de Copenhagen; DinamarcaFil: Moroni, Pablo Daniel. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, FÃsicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: O'Leary, Nataly Cristina. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, FÃsicas y Naturales. Instituto de Botánica Darwinion; Argentin
Adolescence as a vulnerable period for the effects of intrinsic and extrinsic regulators of neurogenesis on cognitive behaviour
Postnatal hippocampal neurogenesis is the birth of new neurons within the dentate gyrus that occurs throughout the lifespan. In adulthood, these new neurons have been shown to be necessary for cognitive tasks such as spatial and contextual memory. It is well established that adult hippocampal neurogenesis can be modulated by a number of intrinsic and extrinsic factors, such as intracellular signalling molecules, exercise, inflammation and stress. Moreover, levels of adult hippocampal neurogenesis do not remain constant throughout life. Indeed, levels of hippocampal neurogenesis and integration of new neurons within the dentate gyrus are up to four times higher during adolescence than during adulthood. The first aim of this thesis (addressed in Chapter 2) was to explore the extent and involvement of Tlx in motor, cognitive and anxietyrelated behaviour. A spontaneous deletion of Tlx, a key intrinsic regulator of neurogenesis, was demonstrated to impair motor, cognitive and anxiety-related behaviours during adolescence and adulthood. The second aim of this thesis (addressed in Chapters 3 and 4) was to investigate the impact of adolescent-initiated exercise on hippocampal plasticity and contextual and cued fear conditioning as well as pattern separation in adulthood. It was demonstrated that adult-initiated exercise enhanced both contextual and cued fear conditioning, while conversely, exercise that began in adolescence did not affect performance in these tasks and these differential effects were accompanied by differential expression of plasticity-related genes in the hippocampus in adulthood. Moreover, adult and adolescent-initiated exercise enhanced cognitive flexibility and dendritic complexity of immature neurons in the dentate gyrus. The third aim of this thesis (addressed in Chapter 5) was to examine the impact of chronically elevated IL-1β on adult hippocampal neurogenesis and pattern separation. It was shown that chronic lentiviral-mediated overexpression of IL-1β within the dorsal hippocampus impaired neurogenesis and performance in its associated cognition, while sparing neurogenesis independent cognition. Finally, the fourth aim of this thesis (addressed in Chapter 6) was to explore the impact of chronic IL-1β, chronic unpredictable stress exposure, or a combination of an initial chronic IL-1β insult was examined following exposure to chronic unpredictable stress on learning and memory and depressive-like behaviours. It was shown that exposure to chronically elevated IL1β and chronic stress independently impair certain types of learning and memory and increased depressive-like behaviour. However, exposure to a sequential ‘two-hit’ of chronically elevated hippocampal IL-1β and chronic stress did not produce an exacerbated phenotype. In summary (Chapter 7), disruption of intrinsic regulators of neurogenesis, such as Tlx, or exposure to extrinsic factors, such as exercise or adverse stimuli, like inflammation and stress, and the consequent effect on cognition may provide insight into why adolescence is a vital period for correct conditioning of hippocampal function in later life
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