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Perforation is one of the many forms of mutilation/manipulation that can be carried out on coin flans, modifying their structure or appearance. After such more or less invasive operations, the coin undertakes a second ‘life’, where it performs different functions from those for which it was manufactured. In some cases, a mutilated specimen may even add a third phase to its ‘biography’, circulating again alongside intact specimens. A great variety characterises the coin perforation, in terms of nominals used, number of holes, size and placement of hole(s), and the method of execution. All these differences suggest multiple and heterogeneous functions for the pierced coins. The paper intends to clarify these functions based on archaeologically excavated finds ‒ as undoubtedly holed during their circulation ‒, and also identify possible re-entries into the exchange circuit. The author also proposes a “Protocol for the Publication of Perforated Coins”, which should allow scholars to understand the consistency, chronological spread and variety of the use of coin perforation even in the western areas of the Roman Empire, although the research carried out so far suggest that the documentation is not particularly abundant.

Security controllers follow the execution of the target systems to prevent security violations. In fact, by proactively observing the target, they are able to catch security violations before they occur and act consequently, such as by interrupting the execution. In this paper we define a novel category of security controllers called lazy controllers, a conservative extension of standard controllers which routinely suspend the observation of the target for different time spans, in order to reduce the cost of monitoring and increase performance, at the expense of the possibility of missing a violation. We show how a proactive truncation controller can be extended to the lazy setting, and we formally characterize the relation between the length of suspended time spans and the actual violation risk, which constitutes the formal ground of our approach. This allows the actual time of suspension to be determined according to a given maximum bearable risk. Precisely, we formally investigate three classes of systems, namely non-deterministic, probabilistic, and stochastic systems. © Springer-Verlag Berlin Heidelberg 2013.

This study presents a joint analysis of the information from 195 field infiltration experiments, using double ring devices. The experiments were carried out in 20 contrasting types of land use, distributed across three geographic contexts (coast of NE Catalonia, low mountains in the central Ebro Valley and mid-height mountains from the southern range of the Central Pyrenees). The objective of this research was to determine the most important factors explaining infiltration variability: land use, type of vegetation cover, soil and bedrock characteristics, soil moisture and altitude. Data analysis was performed by comparing variables using statistical methods: bivariate lineal correlation, ANOVA and Bonferroni multiple comparison tests. Results show that infiltration variability is the most important factor and mainly linked to land use, followed by vegetation type. In contrast, soil moisture did not show any relation with infiltration. The interpretation of these results suggests that the characteristics of the study areas are more decisive than temporal variations of soil water content, although humidity can influence land use to a greater or lesser degree. The validity of the results obtained in this study is supported by the wide range of land use and land cover analysed, located in areas with different geographical and geological characteristics., Este estudio presenta el análisis conjunto de la información obtenida a partir de 195 ensayos de infiltración en el campo, que fueron realizados mediante dispositivos de doble anillo. Los experimentos se realizaron en 20 situaciones contrastadas de usos del suelo, los cuales se encuentran distribuidos en tres contextos geográficos (costa NE de Cataluña, monte bajo del sector central del valle del Ebro y montaña media de la vertiente Sur del Pirineo central). El objetivo de esta investigación es determinar los factores más importantes que explican la variabilidad de la infiltración: uso del suelo, tipo de cubierta vegetal, características del suelo y del substrato rocoso, humedad del suelo y altitud. El análisis de los datos se realizó mediante la comparación de las variables a partir de distintos métodos estadísticos: test de correlación lineal bivariada, ANOVA y comparaciones múltiples de Bonferroni. Los resultados muestran que la variabilidad de la infiltración está principalmente asociada al tipo de uso del suelo, siendo el factor más determinante. El tipo de cubierta vegetal se mostró como el segundo factor en importancia, mientras la humedad del suelo no presentó correlación con la infiltración. La interpretación de estos resultados sugiere que las características de las áreas de estudio son más determinantes que las variaciones temporales del estado hídrico del suelo, aunque la humedad pueda tener un grado de influencia mayor o menor en cada uso del suelo. La validez de los resultados obtenidos en este estudio está avalada porque se ha analizado un amplio espectro de escenarios de uso del suelo/cubierta vegetal, incluso teniendo en cuenta que se han comparado zonas con distintas características geográficas y geológicas.

This study presents a joint analysis of the information from 195 field infiltration experiments, using double ring devices. The experiments were carried out in 20 contrasting types of land use, distributed across three geographic contexts (coast of NE Catalonia, low mountains in the central Ebro Valley and mid-height mountains from the southern range of the Central Pyrenees). The objective of this research was to determine the most important factors explaining infiltration variability: land use, type of vegetation cover, soil and bedrock characteristics, soil moisture and altitude. Data analysis was performed by comparing variables using statistical methods: bivariate lineal correlation, ANOVA and Bonferroni multiple comparison tests. Results show that infiltration variability is the most important factor and mainly linked to land use, followed by vegetation type. In contrast, soil moisture did not show any relation with infiltration. The interpretation of these results suggests that the characteristics of the study areas are more decisive than temporal variations of soil water content, although humidity can influence land use to a greater or lesser degree. The validity of the results obtained in this study is supported by the wide range of land use and land cover analysed, located in areas with different geographical and geological characteristics., Este estudio presenta el análisis conjunto de la información obtenida a partir de 195 ensayos de infiltración en el campo, que fueron realizados mediante dispositivos de doble anillo. Los experimentos se realizaron en 20 situaciones contrastadas de usos del suelo, los cuales se encuentran distribuidos en tres contextos geográficos (costa NE de Cataluña, monte bajo del sector central del valle del Ebro y montaña media de la vertiente Sur del Pirineo central). El objetivo de esta investigación es determinar los factores más importantes que explican la variabilidad de la infiltración: uso del suelo, tipo de cubierta vegetal, características del suelo y del substrato rocoso, humedad del suelo y altitud. El análisis de los datos se realizó mediante la comparación de las variables a partir de distintos métodos estadísticos: test de correlación lineal bivariada, ANOVA y comparaciones múltiples de Bonferroni. Los resultados muestran que la variabilidad de la infiltración está principalmente asociada al tipo de uso del suelo, siendo el factor más determinante. El tipo de cubierta vegetal se mostró como el segundo factor en importancia, mientras la humedad del suelo no presentó correlación con la infiltración. La interpretación de estos resultados sugiere que las características de las áreas de estudio son más determinantes que las variaciones temporales del estado hídrico del suelo, aunque la humedad pueda tener un grado de influencia mayor o menor en cada uso del suelo. La validez de los resultados obtenidos en este estudio está avalada porque se ha analizado un amplio espectro de escenarios de uso del suelo/cubierta vegetal, incluso teniendo en cuenta que se han comparado zonas con distintas características geográficas y geológicas.

This essay examines a deposit of 29 late Roman bronze coins (4th-5th centuries AD) found at Luni (Liguria, North of Italy). They were hidden inside a small hole dug into a mosaic floor and sealed by a layer of mortar. After studying the chronology and the numismatic aspects of the group of coins, the author discusses the way in which the coins were concealed, in an attempt to discern the reason why they were placed inside an architectural structure. That the hoard was hidden to be preserved or to serve as a chronological indicator can be ruled out. The author suggests that the coins were deposited for votive or ritual purposes.