The dust environment of comet 67P/Churyumov-Gerasimenko from Rosetta OSIRIS and VLT observations in the 4.5 to 2.9 au heliocentric distance range inbound

Context. The ESA Rosetta spacecraft, currently orbiting around comet 67P/Churyumov-Gerasimenko, has already provided in situ measurements of the dust grain properties from several instruments,particularly OSIRIS and GIADA. We propose adding value to those measurements by combining them with ground-based observations of the dust tail to monitor the overall, time-dependent dust-production rate and size distribution.
Aims. To constrain the dust grain properties, we take Rosetta OSIRIS and GIADA results into account, and combine OSIRIS data during the approach phase (from late April to early June 2014) with a large data set of ground-based images that were acquired with the ESO Very Large Telescope (VLT) from February to November 2014.
Methods. A Monte Carlo dust tail code, which has already been used to characterise the dust environments of several comets and active asteroids, has been applied to retrieve the dust parameters. Key properties of the grains (density, velocity, and size distribution) were obtained from Rosetta observations: these parameters were used as input of the code to considerably reduce the number of free parameters. In this way, the overall dust mass-loss rate and its dependence on the heliocentric distance could be obtained accurately.
Results. The dust parameters derived from the inner coma measurements by OSIRIS and GIADA and from distant imaging using VLT data are consistent, except for the power index of the size-distribution function, which is α = −3, instead of α = −2, for grains smaller than 1 mm. This is possibly linked to the presence of fluffy aggregates in the coma. The onset of cometary activity occurs at approximately 4.3 AU, with a dust production rate of 0.5 kg/s, increasing up to 15 kg/s at 2.9 AU. This implies a dust-to-gas mass ratio varying between 3.8 and 6.5 for the best-fit model when combined with water-production rates from the MIRO experiment.

1964-65 Board of Governors

The 1964-65 Board of Governors. Pictured here are those who attended the first meeting on December 8, 1964. From left to right - Front Row: E. E. Mitchelson, Niagara Falls. Mrs. J. J. Bench, St. Catharines. W. B. Gunning, Chippawa. Dr. J. A. Gibson, St. Catharines. D. G. Willmot, St. Catharines. J. M. Trott, Welland. C. B. Hill, St. Catharines. A. C. Rae, Fonthill. Back Row: E. S. Howard, Fort Erie. W. J. Freeman, Port Colborne. M. L. Swart, Thorold. C. F. Anderson, Port Colborne. W. S. Martin, Queenston. E. R. Davey, Niagara Falls. R. L. Hearn, Queenston. C. W. Morehead, Welland. S. J. Leishman, Thorold. F. H. Leslie, Chippawa. F. C. Cullimore, Chippawa. W. B. C. Burgoyne, St. Catharines. H. C. Blenkhorn, St. Catharines. M. A. Chown, St. Catharines. B. P. R. Newman, St. Catharines. R. S. Misener, St. Catharines. Missing: R. M. Schmon, Niagara on the Lake. E. J. Barbeau, St. Catharines. P. E. Roberts, Toronto. L. R. Williams, Welland.

Founders Committee

Members of the Founders' Committee. Pictured here in a clockwise fashion from the left are: R. L. Hearn, W. J. Freeman, M. A. Chown, M. L. Swart, C. Bruce Hill, C. B. Slemon, Dr. James A. Gibson, D. G. Willmot, J .M. Trott, A. C. Rae, W. B. C. Burgoyne, E. S. Howard, L. R. Williams, S. J. Leishman, E. J. Barbeau, and E. R. Davey. Missing from the photo were: W. B. Gunning, W. S. Martin, C. W. Morehead, and B. P. R. Newman.

First Degree Bestowed

The first graduate, John Auld, receives his convocation hood from (?) during the first ever Convocation held at Brock in 1967. Chancellor R. L. Hearn stands in front of John Auld.

L'ascendant du double dans Les Caves du Vatican et dans Les Faux-Monnayeurs d’André Gide : personnages et narration

Ce travail explore la dualité telle qu’elle se présente dans deux ouvrages d’André Gide, Les Caves du Vatican et Les Faux-Monnayeurs. Thème majeur de la littérature, le double ne cesse d’illustrer les différentes tensions qui se créent et se combattent chez une seule et même personne. Souvent représenté physiquement dans la littérature du XIXe siècle à la suite de la figure du Doppelgänger, le double chez Gide se complexifie : plus subtil, il se manifeste de manière psychologique. La dualité se présente de deux manières dans les écrits d’André Gide : chez les personnages et à travers la narration. Par l’étude des contradictions et des inconséquences des personnages, de la représentation de la dualité chez différents personnages, de leur dédoublement et de leurs doubles discours, il sera possible de constater à quel point les personnages structurent la dualité. L’analyse de l’identité des narrateurs, de leurs interventions et des figures de rhétorique qu’ils emploient permettra également de comprendre que plus ils se révèlent, plus ils se complexifient.

Building Grounded Abstractions for Artificial Intelligence Programming

Most Artificial Intelligence (AI) work can be characterized as either ``high-level'' (e.g., logical, symbolic) or ``low-level'' (e.g., connectionist networks, behavior-based robotics). Each approach suffers from particular drawbacks. High-level AI uses abstractions that often have no relation to the way real, biological brains work. Low-level AI, on the other hand, tends to lack the powerful abstractions that are needed to express complex structures and relationships. I have tried to combine the best features of both approaches, by building a set of programming abstractions defined in terms of simple, biologically plausible components. At the ``ground level'', I define a primitive, perceptron-like computational unit. I then show how more abstract computational units may be implemented in terms of the primitive units, and show the utility of the abstract units in sample networks. The new units make it possible to build networks using concepts such as long-term memories, short-term memories, and frames. As a demonstration of these abstractions, I have implemented a simulator for ``creatures'' controlled by a network of abstract units. The creatures exist in a simple 2D world, and exhibit behaviors such as catching mobile prey and sorting colored blocks into matching boxes. This program demonstrates that it is possible to build systems that can interact effectively with a dynamic physical environment, yet use symbolic representations to control aspects of their behavior.

Didáctica del inglés para primaria.

Resumen tomado de la publicación. Incluye un glosario

Cosmo and the magic sneeze.

La historia de un gatito blanco y negro llamado Cosmo y sus padres, India y Mephisto. Mephisto es un gato de brujas, un gato que puede utilizar su magia para ayudar a estornudar a una bruja en sus hechizos, mientras que India es un gato doméstico normal. Cosmo tiene que pasar una prueba especial para ver si es más como Mephisto o India. Cuando pasa la prueba especial, es capaz de ayudar a estornudar a la bruja Sybil y llevar a cabo la magia estornudo que añade el ingrediente extra-especial al caldero. Sybil y su madre, Eufemia, están haciendo una poción secreta para un hechizo que produce estatuas de oro y Scarlett, Bunty y Cosmo tienen que averiguar cuáles son los componentes de la poción, antes de que sea demasiado tarde. Sobre todo porque las estatuas tienen forma de gatitos.

Success for schools science 3. Teaching resources photocopiable.

Se apoya en el libro del alumno y cumple los objetivos docentes para la etapa 3 (key stage 3) del nivel de secundaria del plan de estudios inglés. Ofrece a los profesores distintas técnicas para el aprendizaje de las ciencias, unas dirigidas a cada estudiante a nivel individual, otras, para realizar, por parejas, por grupos o toda la clase en conjunto. También, contiene varios sugerencias para actividades prácticas, hojas de trabajo fotocopiables, así como un apartado con las normas de seguridad a seguir en las escuelas en cuanto a materiales, productos químicos y equipos utilizados por los alumnos durante el curso.

Success for schools science : levels 4-7. KS3 framework course.

Cumple con los objetivos docentes para la etapa 3 (key stage 3) del nivel de secundaria del plan de estudios inglés. Se estructura en varias secciones: un repaso del curso anterior, una introducción ó avance de las nuevas ideas del curso presente, las propias unidades de estudio y los objetivos que se han de cumplir con la realización de ejercicios de evaluación. También, se considera un reto en el aprendizaje de las ciencias, la utilización de un vocabulario específico por parte de los estudiantes. Se acompaña de una guía-recurso para el profesor.

Employer matters in 2003

The year 2003 was characterised by employer proactivism, and a preparedness to pursue new legal manoeuvres to prevent or terminate protected industrial action. A number of employers also resorted to lengthy lockouts (with few positive results) as bargaining tactics in enterprise negotiations. It was the year employers in the manufacturing and metals sector saw off the unions’ ‘Campaign 2003’, giving little ground on the key issues of reduced hours and contributions to trust funds for worker entitlements. The year was a joyous one for employers in the building and construction industry, as their dreams of a shackled and weakened union movement came a step closer to being realised, with the introduction of draconian industry-specific legislation by the Howard Government, arising from the recommendations of the Cole Royal Commission. On a positive note, the year also witnessed all the members of the ‘industrial relations club’ embrace and declare a common concern for work and family balance issues.

Employer matters in 2004

n 2004, employers were active in arguing their cases in a number of important hearings of the Australian Industrial Relations Commission. However, despite a united position among employer ranks and the federal government, employers were generally disappointed with the Commission’s safety net review decision. Both the Australian industry Group and the Australian Chamber of Commerce and Industry found some common ground with the Australian Council of Trade Unions, in a consent position on extending carers leave, but overall employers presented a detailed argument opposing any extension of employee rights in the Commission’s work and family test case. Employers in some sectors were able to reach collective agreements with unions with little industrial disruption, whereas others, such as banking, found the going tougher. Overall, employers, like unions, faced a great deal of uncertainty over what were or were not ‘matters pertaining’, as a number of decisions after the Electrolux case clarified or clouded the issue. Understandably, the year ended on a positive note for most employers, with the Howard Government re-elected with a majority in the Senate, enabling it to pass a further round of radical labour market reforms in 2005.

Employer matters in 2005

By any reckoning, the year 2005 will long be remembered as a watershed year for Australian industrial relations. While there were the usual types of industrial disputes, on-going enterprise bargaining and another round of arguments over the Australian Industrial Relations Commission’s (AIRC’s) annual safety-net review, the year was dominated by the looming re-writing of Australia’s industrial relations regulatory regime, made possible by the Government’s surprise majority in the Senate, granted to them in late 2004. Viewed as a looming dark cloud by some or a shining light by others, most of 2005 was spent in anxious anticipation of the Howard government’s impending ‘WorkChoices’ legislation. Employer groups spent much of the year lobbying the Howard government for the types of reforms long cherished, but only dreamed of by employers, for arguably 100 years. A once in a lifetime opportunity had presented itself and employer groups were determined to take full advantage of the situation, by ensuring that the government did not lose its nerve. Perhaps more importantly, however, in addition to lobbying the government, major employer organizations devoted significant resources to building the case for industrial relations reform and attempting to sell that message to the electorate. By year’s end, employers had succeeded in the first objective, but had seemingly failed in the second.

How the west was lost? Hamersley Iron, the birthplace of a decade of De-Unionisation

Given the focus of recent years on Rio Tinto's battles with the Australian union movement over its (largely successful) attempt to de-unionise its diverse mining and manufacturing operations, this paper examines how the company first introduced its 'staff employment system at Hamersley Iron in 1993. The success of this venture clearly provided a template for its replication throughout its many other operations over the following years. Though no doubt assisted by changed legal and political environments, this paper argues that it was ultimately the demonstration of managerial determination and a hesitant union leadership which led to the de-unionisation at Hamersley Iron. As the union movement/makes a renewed attempt to attract workers back to the fold, there are valuable lessons to be learnt from its earlier mistakes.