Vault System Research Articles

Parametric Design of Masonry Vaults Based on Structural Affinity

In this paper a novel method for the design of complex affine vaults is proposed. By merging the thrust line theory with Rankine’s concept of the transformation of structures, the system of complex groin vaults whose constituent parts are mutually affine cylindrical vaults is treated. The method enables the omission of the analysis of the actual structural action within a vault without jeopardising the vault’s stability. That provides simplicity of the overall computation as well as the fast evaluation of the vault’s thrust. The proposed parametric model for the equilibrium analysis of affine vaults is based on the geometrical properties of a suitably chosen initial vault’s part exposed to transformations, where the disposition of supports in a vault’s plan becomes the main input for the computation. The method provides the design of the variety of complex affine vaults, as well as the automated calculation of the resultant loading exerted to supports with their graphical representation.

Pseudo-Static Response of Masonry Cross Vaults to Imposed Shear Displacements at the Springings

The static and dynamic performances of historical masonry churches are closely related to the behaviour of each substructure, as well as to the mechanical properties of the constituent materials. Information on damage location and extent, collected after recent violent Italian earthquakes, highlighted that masonry vaults are among the most vulnerable elements. The investigation of their dynamic behaviour under earthquake excitation (stress and deformation states) is a fundamental issue for effective structural interventions. During an earthquake ground motion, cross vaults are basically subjected to two phenomena: (i) the "shaking"/dynamic response of the vault system itself, vibrating above the lateral walls and piers, and (ii) the response of the vault to imposed displacements at its springings, accommodating the significant movements of the lateral walls and piers. Within this context, this paper aims at improving the knowledge of the structural behaviour of cross vaults under static shear deformation at the springings, by means of an experimental test representative of a Gothic cross vault from the aisle of the Holyrood Abbey in Edinburgh (UK). The experimental test was performed on a 1:4 scaled specimen built with timber and lime mortar. The shear displacement was applied by moving two abutments until failure. The deformation of the vault was recorded in space with a Total Station. The results of the tests are reported in this paper in terms of crack pattern evolution, vertical displacements of the transverse ridge, identifying the shear displacement levels corresponding to significant damages in the vault.

Baroque Turin, Between Geometry and Architecture

In the baroque Turin it is possible to identify routes aimed to discover atria of palaces and houses, freely accessible, whose unitary vaulted systems made of brickworks show an admirable combination of geometry and architecture, making them a case of interest in architectural history (Callet & Lesueurs 1855, Norberg Schultz 1980) for quality, quantity and variety of solutions. Actually, the 'esprit de geometrie' - which permeated the philosophical interests of that period, fueled by the theories of Galileo, Descartes, Pascal and Desargues, - was expressed through the work of extraordinary architects in the city. The theoretical and practical activities of Guarino Guarini, a Theatines abbot who spent the last part of his life in Turin from 1666 to 1683 as an architect, engineer and mathematician to service Carlo Emanuele of Savoy, turned out to be a driving force of this phenomenon. In particular, in Architettura Civile (Guarini 1737), he developed a real vocabulary of shapes, starting from geometric primitives: by combining them a great variety of complex vaulted systems arose. In the transition between the purely geometric concept of vaulted system and its application in palaces, dimensional constraints and construction practices involved adjustments foreseen in the Treaty and experienced by Guarini in the vaults of the atria of Palazzo Carignano and Palazzo Provana di Collegno. These adjustments generated a deviation from the ideal geometric models. In the Eighteenth-Century Giovanni Giacomo Plantery, indirectly linked with Guarini because of the kinship with Bernardo Vittone - the editor of the posthumous publication of Architettura Civile - and his probable apprenticeship with him turned out to be decisive for the experimentation of new compositional solutions that had wide spread along the expansion axes and the reshaping areas of the city.

Un apunte a la problemática constructiva de la Catedral de México: el caso de las cubiertas abovedadas y su replanteo hacia 1628

In 1628 archbishop Francisco de Manso y Zuniga, proposed the construction of vaults for the unfinished Mexico City Cathedral. He counted on the experience of the architect Juan Gomez de Trasmonte, who proposed a system of barrel vaults with lunettes for the central nave and sail vaults for the side aisles. Moreover, Gomez proposed three possible technical solutions for the use of different stone types: chiluca, los Remedios and tezontle. The following year serious flooding and its consequences delayed the execution of these works, but the 1628 plans would seem to be at the origin of the vaults extant today in the three naves of the Cathedral.

An insight in the late Baroque architecture: An integrated approach for a unique Bibiena church

Abstract In this paper a masonry baroque church by Antonio Galli Bibiena in Villa Pasquali is analyzed using a multidisciplinary approach. The importance of this monument is due to the prestige of its architect and to the peculiar system of masonry perforated vaults, which is an unicum in architectural history. Nevertheless, until now this church has not been studied, but historical data and significant crack patterns have pointed out its high vulnerability. The first step related to the knowledge of the building consists of the historical record of archival documents, which allow for the identification of the vulnerable elements. An accurate geometric survey is carried out with Terrestrial Laser Scanning in order to detect the complex three-dimensional geometry of the structure and crack patterns. Finally, a three-dimensional finite element model of the entire structure is developed and a comparison between the numerical results and the damage survey is performed.

Seismic Behavior of Mexican Colonial Churches

ABSTRACTDuring the past two decades, it is growing the interest to study the seismic behavior of old masonry churches in Latin America. The architectural heritage has been seriously damaged by the earthquake activity. The interest to preserve this kind of structures has motivated the study of their dynamical behavior and their seismic vulnerability. The out-of-plane failure of the facade is a frequently damage pattern after strong seismic events in many churches, principally in churches with a gable roof like many churches in Europe. However, in the old masonry churches built in Latin-America and especially in Mexico, the out-of-plane behavior is generally less important and is only regarded with the detachment of the facade from the nave, but without reach the collapse. To understand the reason that the out-of-plane behavior is less important in old Mexican churches, a study of the seismic behavior of this kind of structures was performed. A typical Mexican colonial church was analyzed under different assumptions. It was concluded that the use of masonry vault system, instead of wooden roof helps to reduce the out-of-plane failure of the facade. As well as the towers provide a constraint that reduces the movement out-of-plane, but also increase the in-plane actions, and are also committed themselves to a combined bending and torsion stress.

A parametric investigation of the seismic capacity for masonry arches and portals of different shapes

Masonry arches are typical components of historic buildings throughout the world, and their damage or collapse is very often caused by earthquakes. The first-order seismic assessment of masonry structures can be represented by the equivalent static analysis method, which does not capture all of the dynamics, but provides a measure of the lateral loading that the structure can withstand before collapse. This study aims to understand the stability of unreinforced masonry arches and portals (i.e. buttressed arches) subjected to constant horizontal ground accelerations, combined with the vertical acceleration due to gravity. An analytical model based on limit analysis is developed to describe the relative stability of pointed and basket-handle arches and portals with respect to circular ones, for varying geometry parameters. The equivalent static analysis determines the value of the constant lateral acceleration needed to cause collapse of the structure, which coincides with the minimum peak ground acceleration needed to transform the vaulted system into a mechanism. Predictions of the analytical model are compared with results of numerical modelling by the Discrete Element Method (DEM). This numerical model considers masonry as an assemblage of rigid blocks with no-tension frictional joints, and is based on a time stepping integration of the equations of motion of the individual blocks. The satisfactory agreement between predictions of the two approaches validates the analytical model and verifies the potentials of the discrete element framework as a method of evaluating the quasi-static behavior of unreinforced masonry structures.

GOTHIC CHURCHES IN PARIS ST GERVAIS ET ST PROTAIS IMAGE MATCHING 3D RECONSTRUCTION TO UNDERSTAND THE VAULTS SYSTEM GEOMETRY

Abstract. This paper is part of a research about ribbed vaults systems in French Gothic Cathedrals. Our goal is to compare some different gothic cathedrals to understand the complex geometry of the ribbed vaults. The survey isn't the main objective but it is the way to verify the theoretical hypotheses about geometric configuration of the flamboyant churches in Paris. The survey method's choice generally depends on the goal; in this case we had to study many churches in a short time, so we chose 3D reconstruction method based on image dense stereo matching. This method allowed us to obtain the necessary information to our study without bringing special equipment, such as the laser scanner. The goal of this paper is to test image matching 3D reconstruction method in relation to some particular study cases and to show the benefits and the troubles. From a methodological point of view this is our workflow: - theoretical study about geometrical configuration of rib vault systems; - 3D model based on theoretical hypothesis about geometric definition of the vaults' form; - 3D model based on image matching 3D reconstruction methods; - comparison between 3D theoretical model and 3D model based on image matching;

Multi Biometric Fuzzy Vault Generation Using Chaff Points and Cuckoo Search Optimization

Usage of human physical and behavioural traits for individual identification dates back to the beginning of human civilization. The demand for automation of biometric system was raised as a result of increase in population. Nowadays, in many applications biometric authentication is gaining popularity. However, its performance is still a constraint for its wide scale implementation. In our proposed work, fingerprint and ear are considered as it provides higher performance than unimodal biometric. Our objective is to store the biometric in the database as fuzzy vault, as storing the biometric template directly in to the database weakens the system security. Initially, the input images of fingerprint and ear are pre-processed to filter the noise and to improve the image contrast. From the pre-processed fingerprint, minutiae points are extracted. Upon the pre-processed ear image, the dimension reducing technique, Principal Component Analysis (PCA), is applied to extract global features. Texture feature is also extracted from both the modalities using Local Gabor XOR Patterns (LGXP). To these extracted features cuckoo optimization is applied to generate optimized points. Chaff points are generated, from randomly generated secret keys. These chaff points are fused with optimized points to generate fuzzy vault. The sensitivity, specificity and accuracy are calculated for the cuckoo optimized fuzzy vault authentication system and compared with the non- optimized fuzzy vault system.

A novel multidisciplinary approach toward a better understanding of cranial suture closure: The first evidence of genetic effects in adulthood

The primary objective of this study was to perform new, relevant information about cranial suture closure in adults. Single nucleotide polymorphisms (SNPs) in targeted genes were examined, which encode factors that play an important role in cranial suture development and maintenance. Our hypothesis was that some of these genes and polymorphisms can influence the cranial suture obliteration status in adulthood as well. Ossification of cranial sutures was ascertained according to Meindl and Lovejoy's vault system (1985: Am J Phys Anthropol 68(1):57-66), and peripheral blood samples were collected during autopsy procedure of 106 individuals at the Department of Forensic and Insurance Medicine, Semmelweis University, Hungary. Genotyping of SNPs was conducted using competitive allele-specific polymerase chain reaction KASPar chemistry. Multivariate linear models were used to test whether SNP polymorphism of the investigated genes has a significant effect on the ectocranial suture synostosis in adults. The msh homeobox 1 (MSX1): rs3821947 polymorphism showed significant association with the extent of suture obliteration. Cranial suture closure in adults is a complex, multifactorial process. According to previous results MSX1 has a role in calvarial bone development and it has an effect on sutural mesenchyme in latter postnatal stages. Our results demonstrate MSX1 effects on suture obliteration in adulthood. These findings represent new, relevant information indicating that genetic background can have an impact on cranial suture closure in adults.

HBIM for Documentation, Dissemination and Management of Built Heritage. The Case Study of St. Maria in Scaria d'Intelvi

The research presented here is carried out within the INTERREG EU project framework, which aims to the valorisation and dissemination of the role of the Church of St. Maria di Scaria (Como, Italy). It mainly focuses on the Carloni's intervention (XVIII century), a local family of craftsmen, famous across many European cities and regions contributing to the construction of monuments and their rich decoration apparatus. The laser scanning and photogrammetric surveys have been integrated with the on-site stratigraphic analysis and with the scarcely available historical documents, in an attempt to focus on the reconstruction of the main transformations and chronological phases: BIM approach has been experimented as a way of transmitting a piece of the history of the church life to the local people and for tourist purposes. A Historic Building Information Modeling (HBIM) has been developed while investigating the potential of an object library specially generated to illustrate the structural elements, the construction technologies, and the decorative layers, along with the critical aspects faced by standard BIM in a complex geometry shift from surface approach to object modeling. The research contributes to the explanation of the sequence and construction technologies adopted for the vault system, the first two vaults of the nave, with respect to the vault covering the altar and the apse. The HBIM approach development is analysed to help the generation of a vocabulary and an abacus of elements to be geographically referenced across Europe to disseminate typical construction elements and skills.

Privacy and Security Assessment of Biometric Template Protection

Abstract Template-Protection-Techniken stellen eine wichtige Ergänzung zu biometrischen Systemen, um das gewünschte Sicherheitsniveau zu erreichen und die Anforderungen an den Schutz der Privatsphäre zu erfüllen. Diese Techniken ermöglichen Erneuerung und Widerruf der Referenzendaten in biometrischen Systemen. In dieser Arbeit wird ein systematisches Evaluierungsframework entwickelt, das sich an die wesentlichen Kriterien und Anforderungen an biometrische Template-Protection-Verfahren festhält. Seine Anwendbarkeit wird durch die Analyse der verschiedenen Algorithmen demonstriert. Die in dieser Arbeit präsentierte Evaluierung ist grundlegend für eine vollständige Analyse. Darüber hinaus ermöglicht es einen Nachweis der Sicherheit und Einhaltung der Privatsphäre. Es schafft eine Basis für Zertifizierung und Benchmark der Template-Protection-Verfahren.

Analytical and experimental studies on seismic behavior of double-layer barrel vault systems with different open angles

This paper presents the seismic behavior of double-layer barrel vault systems with different open angles through analytical and experimental studies with modeling of thin-walled steel tubes. For the analytical study, different six open angles and four fundamental frequencies were incorporated into the barrel vault analysis models and analyzed. A total of 24 double-layer structures were developed using the MIDAS computer analysis program and these structures were subjected to three different ground motions with a 5% damping ratio. The characteristics of the dynamic responses for the X, Y, and Z directions of the analytical model, subjected to both horizontal and vertical earthquakes, were investigated. In addition to the analytical study, an experimental study using scaled down thin-walled steel tube models was undertaken using a shaking table test. Comparing the analytical and experimental studies, the dynamic behaviors were very similar in terms of the distributions of the acceleration responses. Both the analytical and experimental models had maximum values at the 1/4 and 3/4 nodes, while having relatively smaller responses at the center node from horizontal earthquakes. It is believed that the barrel vault model with an open angle of 90 degrees has the most advantageous shape of the analytical barrel vault models used in this study.

A New Palm Print Based Fuzzy Vault System for Securing Cryptographic Key

A New Palm Print Based Fuzzy Vault System for Securing Cryptographic Key

Parallel Processing of the Fuzzy Fingerprint Vault based on Geometric Hashing

User authentication using fingerprint information provides convenience as well as strong security. However, serious problems may occur if fingerprint information stored for user authentication is used illegally by a different person since it cannot be changed freely as a password due to a limited number of fingers. Recently, research in fuzzy fingerprint vault system has been carried out actively to safely protect fingerprint information in a fingerprint authentication system. In addition, research to solve the fingerprint alignment problem by applying a geometric hashing technique has also been carried out. In this paper, we propose the hardware architecture for a geometric hashing based fuzzy fingerprint vault system that consists of the software module and hardware module. The hardware module performs the matching for the transformed minutiae in the enrollment hash table and verification hash table. On the other hand, the software module is responsible for hardware feature extraction. We also propose the hardware architecture which parallel processing technique is applied for high speed processing. Based on the experimental results, we confirmed that execution time for the proposed hardware architecture was 0.24 second when number of real minutiae was 36 and number of chaff minutiae was 200, whereas that of the software solution was 1.13 second. For the same condition, execution time of the hardware architecture which parallel processing technique was applied was 0.01 second. Note that the proposed hardware architecture can achieve a speed-up of close to 100 times compared to a software based solution.

A novel algorithm of fingerprint encryption using minutiae-based transformation

This paper presents a novel algorithm of fingerprint encryption which transforms fingerprint minutiae and performs matching in the transformed form. If an encrypted template is compromised, it can be cancelled by choosing just another transformed template. In our algorithm, a circular region is constructed around each minutia and non-invertible transformation is applied to all regions but only transformed regions are stored in the database. The proposed algorithm improves the accuracy of verification compared to related fuzzy vault systems. Experimental results show the comparative performance of matching using both transformed and original data. We find that transformed matching also has an impressive accuracy and speed.

VLSI implementation of the fuzzy fingerprint vault system

Biometrics-based user authentication has several advantages over traditional password-based systems for standalone authentication applications. The fingerprint is evaluated as the most realistic alternative up to the present time in the perspectives of availability, accuracy and economy. However, serious problems may cause if fingerprint information stored for user authentication is used illegally by a different person since it cannot be changed freely as a password due to a limited number of fingers. Recently, research in fuzzy fingerprint vault system has been carried out actively to safely protect fingerprint information in a fingerprint authentication system. In this paper, we propose the FPGA-based fuzzy fingerprint vault system for real-time processing. Based on the experimental results, we confirmed that the proposed system takes 0.53 second with 36 real minutiae and 400 chaff minutiae.

A New Method for Generating an Invariant Iris Private Key Based on the Fuzzy Vault System

Cryptographic systems have been widely used in many information security applications. One main challenge that these systems have faced has been how to protect private keys from attackers. Recently, biometric cryptosystems have been introduced as a reliable way of concealing private keys by using biometric data. A fuzzy vault refers to a biometric cryptosystem that can be used to effectively protect private keys and to release them only when legitimate users enter their biometric data. In biometric systems, a critical problem is storing biometric templates in a database. However, fuzzy vault systems do not need to directly store these templates since they are combined with private keys by using cryptography. Previous fuzzy vault systems were designed by using fingerprint, face, and so on. However, there has been no attempt to implement a fuzzy vault system that used an iris. In biometric applications, it is widely known that an iris can discriminate between persons better than other biometric modalities. In this paper, we propose a reliable fuzzy vault system based on local iris features. We extracted multiple iris features from multiple local regions in a given iris image, and the exact values of the unordered set were then produced using the clustering method. To align the iris templates with the new input iris data, a shift-matching technique was applied. Experimental results showed that 128-bit private keys were securely and robustly generated by using any given iris data without requiring prealignment.

Structural Behaviour Of Gothic Vaults

For a long period of time Gothic vaults have been one of the most controversial elements of Gothic constructions. The rib vault system that supports the infill, and its indisputable efficacy has brought about numerous studies and hypotheses. Some, following Viollet-le Duc, consider the ribs as unique in effectiveness; others, sharing Pol Abraham's opinion, consider them to be totally useless. For several years our team has been working on systems of modelling and calculus of historic buildmgs, which are generally of stone in Spain. In this research we have paid much attention to the structures of great Gothic buildings of the northeast of the peninsula and especially to the modelling of their vaults. Due to the research carried out we have been able to produce applications and programmes that could be used in the general study of G o h c vaults. Tbis paper gives analyses of diverse Goth~c vaults with different modellings and most relevant conclusions of their structural behaviour.

An introduction to the history of structural mechanics: Pt. 1: Statics and resistance of solids; Pt. 2: Vaulted structures and elastic systems

An introduction to the history of structural mechanics: Pt. 1: Statics and resistance of solids; Pt. 2: Vaulted structures and elastic systems