936 resultados para falling initial distributions of deuterio-isomers
Resumo:
The transfer of gases between the atmosphere and ocean is affected by a number of processes, of which wave action and rainfall are two of potential significance. Efforts have been made to quantify separately their contributions; however such assessments neglect the interaction of these phenomena. Here we look at the correlation statistics of waves and rain to note which regions display a strong association between rainfall and the local sea state. The conditional probability of rain varies from ~0.5% to ~15%, with most of the equatorial belt (which contains the ITCZ) showing a greater likelihood of rain at the lowest sea states. In contrast the occurrence of rain is independent of wave height in the Southern Ocean. The 1997/98 El Niño enhances the frequency of rain in some Pacific regions, with this change showing some association with wave conditions.
Resumo:
The AltiKa altimeter records the reflection of Ka-band radar pulses from the Earth’s surface, with the commonly used waveform product involving the summation of 96 returns to provide average echoes at 40 Hz. Occasionally there are one-second recordings of the complex individual echoes (IEs), which facilitate the evaluation of on-board processing and offer the potential for new processing strategies. Our investigation of these IEs over the ocean confirms the on-board operations, whilst noting that data quantization limits the accuracy in the thermal noise region. By constructing average waveforms from 32 IEs at a time, and applying an innovative subwaveform retracker, we demonstrate that accurate height and wave height information can be retrieved from very short sections of data. Early exploration of the complex echoes reveals structure in the phase information similar to that noted for Envisat’s IEs.
Resumo:
R-matrix calculated photoelectron angular distribution asymmetry parameters, beta for Cl+ 3s3p(5) P-3(o) and 3s(2)3p(3) (D-2(o))3d P-1(o) final ionic states in photoionization of the ground state of atomic Cl are presented in the photon energy range from threshold to 80 eV. The results, characterized by prominent autoionization structures which are sensitive to multielectron correlations, are compared with those recently measured by Whitfield et al (Whitfield S B, Kehoe K, Krause M 0 and Caldwell C D 2000 Phys. Rev. Lett. 84 4818). Contrary to experiment and previous theoretical calculations, our detailed CIV3 structure calculation (Deb N C, Crothers D S F, Felfli Z and Msezane A Z 2002 J. Phys. B: At. Mol. Opt. Phys. submitted) has identified the lowest P-1(o) level of Cl+ as 3S(2)3p(3)(D-2(o))3d P-1(o) rather than 3s3p(5) P-1(o). The implications and consequences of the measured data for the 3s P-1(o) level are also discussed in the context of our calculated energies for Cl+ and beta for 3d P-1(o).
Resumo:
This paper seeks to analyse some key issues related to initial training models for secondary education teachers from an international perspective with more specific references to the Spanish model. First, we briefly mention secondary education and its training needs: purpose, organization, structure, character, duration, etc.. Secondly, the most typical models of initial training of these teachers: consecutive and simultaneous, academic and professional, are adressed. Thirdly, we analyse the structure of initial training containing more general scientific and professional knowledge, (its theoretical and practical components). Lastly, the relationship between initial training and access to the teaching profession will be established, as well as the possibility of academic and / or professional qualifications is analyzed. We then highlight the issue of "professional identity", which is closely linked to the initial training of future teachers and final conclusions are discussed.
Investigation of a multimarker approach to the initial assessment of patients with acute chest pain.
Resumo:
Research into student teachers' perceptions, attitudes and prior experiences of learning suggests that these experiences can exert an influence on practice which can be relatively undisturbed by their initial teacher education. This article is based on the initial findings of an all-Ireland survey of all first-year students on B.Ed. courses in colleges in Northern Ireland and in the Republic of Ireland. The survey is the first stage in a longitudinal study which will follow the same cohort of students for the duration of their initial teacher education, seeking to map and track the development of their ideas about teaching and learning in primary history, geography and science. Based on an analysis of the quantitative data in the entry questionnaire, the initial findings suggest that subject knowledge remains a problematic issue in initial teacher education and that both location and gender interact with knowledge, attitudes and subject area to produce a complex and challenging context for teacher educators in history, geography and science education.
Resumo:
The aim in this study was to determine the outcomes of boost stereotactic radiosurgery, specifically Gamma Knife surgery (GKS), for recurrent primitive neuroectodermal tumors (PNETs) in children in whom initial multimodality management had failed.