904 resultados para INFORMATION EXTRACTION FROM DOCUMENTS


Relevância:

100.00% 100.00%

Publicador:

Resumo:

OBJECTIVES: To determine the prevalence of false or misleading statements in messages posted by internet cancer support groups and whether these statements were identified as false or misleading and corrected by other participants in subsequent postings. DESIGN: Analysis of content of postings. SETTING: Internet cancer support group Breast Cancer Mailing List. MAIN OUTCOME MEASURES: Number of false or misleading statements posted from 1 January to 23 April 2005 and whether these were identified and corrected by participants in subsequent postings. RESULTS: 10 of 4600 postings (0.22%) were found to be false or misleading. Of these, seven were identified as false or misleading by other participants and corrected within an average of four hours and 33 minutes (maximum, nine hours and nine minutes). CONCLUSIONS: Most posted information on breast cancer was accurate. Most false or misleading statements were rapidly corrected by participants in subsequent postings.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

We address under what conditions a magma generated by partial melting at 100 km depth in the mantle wedge above a subduction zone can reach the crust in dikes before stalling. We also address under what conditions primitive basaltic magma (Mg # >60) can be delivered from this depth to the crust. We employ linear elastic fracture mechanics with magma solidification theory and perform a parametric sensitivity analysis. All dikes are initiated at a depth of 100 km in the thermal core of the wedge, and the Moho is fixed at 35 km depth. We consider a range of melt solidus temperatures (800-1100 degrees C), viscosities (10-100 Pa s), and densities (2400-2700 kg m(-3)). We also consider a range of host rock fracture toughness values (50-300 MPa m(1/2)) and dike lengths (2-5 km) and two thermal structures for the mantle wedge (1260 and 1400 degrees C at 100 km depth and 760 and 900 degrees C at 35 km depth). For the given parameter space, many dikes can reach the Moho in less than a few hundred hours, well within the time constraints provided by U series isotope disequilibria studies. Increasing the temperature in the mantle wedge, or increasing the dike length, allows additional dikes to propagate to the Moho. We conclude that some dikes with vertical lengths near their critical lengths and relatively high solidus temperatures will stall in the mantle before reaching the Moho, and these may be returned by corner flow to depths where they can melt under hydrous conditions. Thus, a chemical signature in arc lavas suggesting partial melting of slab basalts may be partly influenced by these recycled dikes. Alternatively, dikes with lengths well above their critical lengths can easily deliver primitive magmas to the crust, particularly if the mantle wedge is relatively hot. Dike transport remains a viable primary mechanism of magma ascent in convergent tectonic settings, but the potential for less rapid mechanisms making an important contribution increases as the mantle temperature at the Moho approaches the solidus temperature of the magma.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A new technique to porewater extraction from claystone employs advective displacement of the in situ porewater by traced artificial porewater. Monitoring of tracer breakthrough yields species-specific transport properties. Results for Opalinus Clay from the Mont Terri Research Laboratory indicate that the chemical disturbances due to the method are minimal, and the observed significant differences in transport properties for Br– and 2H are in agreement with existing data. Sampling times are 2–4 months, and observation of tracer breakthrough takes 12–24 months at hydraulic conductivity of ∼10-13 m/s.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Information integration is a very important topic. Reusing the knowledge and having common and exchangeable representations have been an active research topic in process systems engineering. In this paper we deal with information integration in two different ways, the first one sharing knowledge between different heterogeneous applications and the second one integrating two different (but complementary) types of knowledge: functional and structural. A new architecture to integrate these representation and use for several purposes is presented in this paper.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Background: Minimally invasive surgery creates two technological opportunities: (1) the development of better training and objective evaluation environments, and (2) the creation of image guided surgical systems.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This article summarizes research on the application of a conductive cement paste as an anode in the now classical technique of electrochemical extraction of chlorides applied to a concrete structural element by spraying the paste on the surface of a concrete structural element, a pillar. Sprayed conductive cement paste, by adding graphite powder, is particularly useful to treat sizable vertical surfaces such are structural supports. Outcomes indicate that this kind of anode not only provides electrochemical chloride removal with similar efficiency, but also is able to retain moisture even without the use of a continuous dampening system.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Material completo EIT