Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - preliminary results

We present the results of a Monte Carlo technique to calculate the absolute magnitudes (H) and slope parameters (G) of about 240,000 asteroids observed by the Pan-STARRS1 telescope during the first 15 months of its 3-year all-sky survey mission. The system's exquisite photometry with photometric errors asteroids rotation period, amplitude and color to derive the most-likely H and G, but its major advantage is in estimating realistic statistical+systematic uncertainties and errors on each parameter. The method was confirmed by comparison with the well-established and accurate results for about 500 asteroids provided by Pravec et al. (2012) and then applied to determining H and G for the Pan-STARRS1 asteroids using both the Muinonen et al. (2010) and Bowell et al. (1989) phase functions. Our results confirm the bias in MPC photometry discovered by ( Jurić et al., 2002).

A 250-year periodicity in Southern Hemisphere westerly winds over the last 2600 years

Southern Hemisphere westerly airflow has a significant influence on the ocean–atmosphere system of the mid- to high latitudes with potentially global climate implications. Unfortunately, historic observations only extend back to the late 19th century, limiting our understanding of multi-decadal to centennial change. Here we present a highly resolved (30-year) record of past westerly wind strength from a Falkland Islands peat sequence spanning the last 2600 years. Situated within the core latitude of Southern Hemisphere westerly airflow (the so-called furious fifties), we identify highly variable changes in exotic pollen and charcoal derived from South America which can be used to inform on past westerly air strength. We find a period of high charcoal content between 2000 and 1000 cal. years BP, associated with increased burning in Patagonia, most probably as a result of higher temperatures and stronger westerly airflow. Spectral analysis of the charcoal record identifies a pervasive ca. 250-year periodicity that is coherent with radiocarbon production rates, suggesting that solar variability has a modulating influence on Southern Hemisphere westerly airflow. Our results have important implications for understanding global climate change through the late Holocene.

A psychosocial approach to understanding pilot and controller acceptance of change in ATM, based on three CDA case studies

Next generation ATM systems cannot be implemented in a technological vacuum. The further ahead we look, the greater the likely impact of societal factors on such changes, and how they are prioritised and promoted. The equitable sustainability of travel behaviour is rising on the political agenda in Europe in an unprecedented manner. This paper examines pilot and controller attitudes towards Continuous Descent Approaches (CDAs). It aims to promote a better understanding of acceptance of change in ATM. The focus is on the psychosocial context and the relationships between perceived societal and system benefits. Behavioural change appeared more correlated with such benefit perceptions in the case of the pilots. For the first time in the study of ATM implementation, and acceptance of change, this paper incorporates the Seven Stages of Change model, based on the constructs of the Theory of Planned Behaviour. It employs a principal components (factor) analysis, and further explores the intercorrelations of benefit perceptions, known in psychology as the ‘halo effect’. Disbenefit perceptions may break down this effect, it appears. For implementers of change, this evidence suggests an approach in terms of reinforcing the dominant benefit(s) perceived, for sub-groups within which a halo effect is evident. In the absence of such an effect, perceived disbenefits, such as with respect to workload and capacity, should be off-set against specific, perceived benefits of the change, as far as possible. This methodology could be equally applied to other stakeholders, from strategic planners to the public. The set of three case studies will be extended beyond CDA trials. A set of concise guidelines will be published with a strong focus on practical advice, in addition to continued work enabling a better understanding of the expected, increasing psychosocial contributions to successful and unsuccessful efforts at ATM innovation and change.

Liste ordinaire de 280 actions et 250 dixièmes d'action tirés à la loterie de la Compagnie des Indes le 26 juin 1730...

[Acte. 1730-06-26]

Français 250

Contient : 1° Histoire ancienne, depuis la création ; 2° « Le Fait des Rommains, composé ensemble de SALUSTE et de SUETOINE et de LUCAN »

Resolución N° 250 del 14 de noviembre de 2007 ¿Pueden los acreedores intervenir en reformas estatutarias dentro de empresas en procesos de restructuración?

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A los 250 años de tu nacimiento : gracias Mozart.

Se celebra el Año Mozart con motivo del 250 aniversario de su nacimiento. El compositor viaja por toda Europa, pero siempre con problemas económicos y muere endeudado. Sus creaciones musicales y éxitos se reparten entre Bolonia, Florencia, Mantua, Milán, Munich, Nápoles y otras ciudades europeas. Su prolífica obra se compone de óperas como La flauta mágica, Don Giovanni, Las Bodas de Fígaro o Cossi fan Tutte; 25 Conciertos para Piano y Orquesta; 6 Conciertos para Violín y Orquesta; 12 conciertos para otros instrumentos; 49 sinfonías; La Marcha Turca o El Réquiem. Además, se utilizan las múltiples posibilidades técnicas y expresivas de la voz en sus obras y se investigan las cualidades de su música para potenciar el desarrollo de pensamientos complejos, como el que requieren las matemáticas.

Actividades matemáticas con materiales didácticos : más de 250 problemas con fichas, dominó, palillos, tramas, geoplanos, policubos, tangram, pentominós, libro de espejos, tabla de multiplicar y papiroflexia.

Contiene: 1. Bases metodológicas y didácticas - 2. Actividades: fichas, dominó..., trama triangular y trama circular - 3. Actividades: policubos..., tabla de multiplicar y papiroflexia