Position-Based Aggregator Node Election in Wireless Sensor Networks

We introduce PANEL a position-based aggregator node election protocol for wireless sensor networks. The novelty of PANEL with respect to other aggregator node election protocols is that it supports asynchronous sensor network applications where the sensor readings are fetched by the base stations after some delay. In particular, the motivation for the design of PANEL was to support reliable and persistent data storage applications, such as TinyPEDS; see the study by Girao et al. (2007). PANEL ensures load balancing, and it supports intra and intercluster routing allowing sensor-to-aggregator, aggregator-to-aggregator, base station-to-aggregator, and aggregator to-base station communications. We also compare PANEL with HEED; see the study by Younis and Fahmy (2004) in the simulation environment provided by TOSSIM, and show that, on one hand, PANEL creates more cohesive clusters than HEED, and, on the other hand, that PANEL is more energy efficient than HEED.

Le triptyque de la Sainte Famille au travail de Pedralbes, une oeuvre flamande 'hispanisée'

This article focuses on a Flemish triptych dating from 1530-1540; it is kept in the convent of Clares Santa Maria de Pedralbes (Barcelona), and can be attributed to the workshop of Pieter Coeck of Aelst. On the central panel is a representation of the Holy Family at work. In order to depict this less well-known theme the artist resorted to several models: Durer's woodcut from the Marienleben, another woodcut which was printed in the convent of Onze-Lieve-Vrouw ten Troost in Vilvoorde (Brussels) and a composition known to us from a version of the Master of the Antwerp Adoration belonging to the Stedelijk Museum in Delft. Due to its unusual iconographical programme we may assume that the triptych was commissioned by a Spanish Clare. The presence of Saints Clare and Agnes on the left-hand panel and of Saint Francis on the right-hand panel strongly suggests that the work was meant for a convent. Normally, female saints would have been on the right-hand side and Saint Francis on the left, in keeping with the heraldic conventions for males and females on Flemish triptychs. However, the Spanish Clare, who surely had contacts with the painter, wanted a more privileged place for women on 'her' triptych, ad dexteram Christi. In 1540-1560 the triptych, together with three other paintings, was converted into the form of an Iberian retable, which bears the arms of Mother Teresa de Cardona, who had probably commissioned the Flemish triptych. It looks less exotic in its new configuration of a more Spanish character. One might speak of a certain normalization that is not just aesthetic but iconographic too. When the triptych was inserted into the retabló, its wings were exchanged, so that the female saints now stand on the right side of the central panel, a position that is surely more in keeping with the prevailing conventions.

De Meester van de Magdalena-legende en de diptiek van Willem van Bibaut

Within the range of works attributed to the Master of the Magdalen Legend are a number of Madonnas generally considered to date back to the last decade of the 15th century. All of these pictures are comparatively small and show a rather chubby type of Madonna with the Child slightly out of proportion. The golden backgrounds are punctuated. All these pictures are by the same hand, and are considered to date from the earliest period of the artist's activity. One of these paintings, now in the Mayer-Van den Bergh Museum in Antwerp, shows the Madonna holding the Child at her left breast. There is a second version of this painting on the left-hand panel of a diptych formerly in the Wetzlar collection in Amsterdam. The right-hand panel bears the portrait of a Carthusian monk, and is inscribed Guilelmus bibaucis primas tot [ius] Ordinis Carthusiemum. 1523.. The sitter has been identified as Willem of Bibaut (1484 1535), who became abbot of the Grand Chartreuse monastery in Grenoble in 1521. The portrait was probably painted to commemorate that event. Given that the stylistically very different paintings belonging to the Magdalen altarpiece which gave the artist his name date from the same period, the Madonnas can no longer be regarded as early paintings by the Master of the Magdalen Legend. Apparently they are the work of another artist.

Corrigenda, Vol. 60

Page 554: H. Bark and S. M. Scharf. “Diaphragmatic blood flow in the dog.” Page 556: in Table 1, the last two entries for Pdi should read: (See PDF) Page 558: in Fig. 5, the graphs labeled “0.2” and “0.8” in the right-hand panel, the X-axis is correct but the midpoint should read: 17.5.