Absolute Calibration of the Auger Fluorescence Detectors

Absolute calibration of the Pierre Auger Observatory fluorescence detectors uses a light source at the telescope aperture. The technique accounts for the ombined effects of all detector components in a single measurement. The calibrated 2.5 m diameter light source fills the aperture, providing uniform illumination to each pixel. The known flux from the light source and the response of the acquisition system give the required calibration for each pixel. In the lab, light source uniformity is studied using CCD images and the intensity is measured relative to NIST-calibrated photodiodes. Overall uncertainties are presently 12%, and are dominated by systematics.Comment: 4 pages, 3 figure. Submitted to the 29th ICRC, Pune, Indi

SEISMIC VULNERABILITY ASSESSMENT OF FES MEDINA IN MOROCCO

Abstract. The assessment of seismic vulnerability in the Maghreb area is not yet fully investigated, especially considering the important connection between the vulnerability and traditional housing or construction local types. This paper proposes a methodology for the assessment of seismic vulnerability at territorial scale that is calibrated on the specific characteristics of historical settlements in the North of Morocco, mostly made of patio buildings in aggregate. The proposed methodology is structured to be extended and replicated in other similar contexts and is based on the Vulnerability Index approach proposed by the National Group for Earthquake Defence (Gruppo Nazionale per la Difesa dai Terremoti, GNDT). This method was applied to the Medina of Fes, UNESCO World Heritage site, which has suffered severe damages from historical earthquakes. The study allowed the realization of vulnerability and fragility curves, damage scenarios for different seismic intensity and loss scenarios. The proposed methodology was applied a second time to the case study after a simulated structural retrofitting intervention. The results of this second application allowed to validate the guidelines and the reinforcement strategies calibrated on local construction culture. The results of the vulnerability assessment are also presented through maps in the Geographic Information System (GIS) environment

Absolute Calibration of a Large-diameter Light Source

A method of absolute calibration for large aperture optical systems is presented, using the example of the Pierre Auger Observatory fluorescence detectors. A 2.5 m diameter light source illuminated by an ultra--violet light emitting diode is calibrated with an overall uncertainty of 2.1 % at a wavelength of 365 nm.Comment: 15 pages, 8 figures. Submitted to JINS

Multi-wavelength Calibration Procedure for the Pierre Auger Observatory Fluorescence Detectors

We present a method to measure the relative spectral response of the Pierre Auger Observatory Fluorescence Detector. The calibration was done at wavelengths of 320, 337, 355, 380 and 405 nm using an end-to-end technique in which the response of all detector components are combined in a single measurement. A xenon flasher and notch-filters were used as the light source for the calibration device. The overall uncertainty is 5%.Comment: Submitted to Astroparticle Physics. V2: section 5.2 extended; author list change

THE DESERT ROSE DOMES OF THE SOUF REGION (ALGERIA). PRELIMINARY EVALUATIONS ON THE VULNERABILITY OF A UNIQUE VERNACULAR HERITAGE

Abstract. The vernacular architecture of the Souf region in Algeria, a desert environment where wood is rare, presents multiple heritage values due to the way in which local materials (especially the desert rose stone) are exploited to build houses and erect distinctive domes. Unfortunately, extensive damage and abandonment compromise the stability of these buildings and accelerate their disappearance, which would negatively affect the urban landscape and the identity of the region. In order to safeguard this unique vernacular heritage, the study focuses on the definition of the typical typology of building, its structural and geometric characteristics, explaining the constructive technique used. Recurrent damage and pathologies that threaten this building culture are also highlighted. Then, estimation of mechanical parameters of the desert rose stone masonry is carried out defining typical characteristics according to the evaluation of the respect of "the rule of the art". Results are then used to perform numerical simulations of the structural behaviour of a typical building, through the finite element method with linear and nonlinear approaches. In particular, the structural behaviour of the dome has been investigated, being the most vulnerable element of the system

DIAGNOSIS PROCESSES FOR DESERT ROSE DOMES OF THE SOUF REGION IN ALGERIA

In the Souf region of Algeria, all vernacular buildings are covered by domes, built with an unusual building material, the desert rose stone, peculiar to the region. These domes represent an element of identity of the region and describe a unique urban landscape that deserves to be protected and enhanced. Unfortunately, these architectural elements have suffered damage that devalues the urban landscape compromising their conservation. In particular, many domes have severe cracks and have collapsed in large areas.Diagnostic investigations were carried out with the aim to understand the causes of the damages and to carry out guidelines for consolidation.In particular, in situ surveys have allowed to analyze the employed construction technique, the collection of samples for the chemical-physical and mechanical investigations of the materials and a manual geometric survey of a typical building module. In addition, a Finite Element Model of a building module was realized with the aim of investigating structural behavior.Considerations were made on the influence of the dome shape on structural behaviour and on the fractures pattern detected in many domes.</p

Seismic Vulnerability Assessment of a 17th Century Colonial Adobe Church in the Central Valley of Chile

This paper focuses on the seismic vulnerability assessment of the San Judas Tadeo´s church in Malloa (Chile), an iconic example of Colonial Chilean architecture. This small adobe structure is a single-nave building consisting of the main nave, a bell-tower located in the façade, two external wooden galleries and additional units such as the sacristy, chapel, and two services areas. The Church has survived several strong earthquakes larger than Mw&gt;8. Besides, after the February 27th, 2010 Maule event it showed remarkable resilience due to the implementation of traditional timber retrofits inserted in the earthen walls. The use of traditional wooden devices such as bond beams, corner keys, and wooden gables, proved to be effective solutions against strong earthquakes. Therefore, this church appears as a relevant case of the use of seismic resistant constructive techniques of the17th century colonial architecture and the study of its seismic behaviour holds great interest and relevance. Aimed to assess the seismic performance of the monument, a complete preliminary study of the church was carried out using a multi-level approach comprising historical research, in situ surveys, crack pattern analysis, physical and mechanical characterization of materials, and structural analyses. In particular as part of an ongoing research, linear and incremental kinematic approaches of limit analyses have been employed with the aim of interpreting the local mechanisms activated during the 2010 Maule earthquake. In these models, the effect of friction on masonry-to-masonry and timber-to-masonry interfaces was considered with promising outcomes. This study results prove the general validity in the field of timber seismic retrofitting of unreinforced adobe buildings

Seismic Vulnerability Assessment of a 17th Century Colonial Adobe Church in the Central Valley of Chile

n/