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The response of vaulted structures with dry-joints such as arches and shells can be predicted using graphical methods, limit state analysis, and rigid block analysis. However, these approaches assume material deformations are negligible. While acceptable for conventional masonry structures, there is a growing body of work investigating segmented vaulted structures where the segments comprise a large portion of the overall span. In such cases, material deformations and non-linearities can play a significant role. Typical analysis tools available are usually difficult to use and are not widely used by industry practitioners. In this paper, a modelling approach using a widely used finite element analysis package (LS-DYNA) is presented, using an ‘out-of-the-box’ approach for parameter tuning and modelling. This was then benchmarked against five experimental tests of dry-joint arches undergoing support displacements and a segmented concrete shell with large segments tested under a central point load. Crucially, the segmented shell exhibited imperfect dry-joints, with gaps occurring throughout various locations. A method of modelling and assessing such imperfections in a simple and practical manner is investigated through the use of a positive penetration allowance in the contact surfaces. The results show that the modelling approach is able to predict the collapse mechanism and failure support displacement for arches well, with further experimental tests required for 3D systems. It is envisioned that this work will add to the number of tools designers will have for analysing segmented vaulted structures with dry-joints.

Tie-rods fixed in different ways in arch and column (pillar) junction areas of historical structures are frequently encountered. These tension members used to sustain the stability of arches play a significant role in the survival of the whole building. In this study, the effect of different tie-rod systems that are fixed on stone arches on the overall behavior of arch is investigated. In the scope of this study, seven stone arches, one reference with no tie-rod, and six repaired using different tie-rod systems were tested under vertical loading. Tested specimens were also analyzed numerically using a commercial computer program called LUSAS. The data obtained as a result of the experiments and the outputs obtained from the numerical models were compared with each other. The main aim of this research is to examine the efficiency, viability, and practicality of replacement techniques recommended for tie-rods in historic masonry stone arches. At the end of the study, the difficulties in the application of tie-rod systems in restoration and strengthening works are examined and the most suitable tie-rod system is revealed by drawing attention to mistakes made during restoration works.

The presence of massive stars (MSs) in the region close to the Galactic Center (GC) poses several questions about their origin. The harsh environment of the GC favors specific formation scenarios, each of which should imprint characteristic kinematic features on the MSs. We present a 2D kinematic analysis of MSs in a GC region surrounding Sgr A* based on high-precision proper motions obtained with the Hubble Space Telescope. Thanks to a careful data reduction, well-measured bright stars in our proper-motion catalogs have errors better than 0.5 mas yr$^{-1}$. We discuss the absolute motion of the MSs in the field and their motion relative to Sgr A*, the Arches and the Quintuplet. For the majority of the MSs, we rule out any distance further than 3-4 kpc from Sgr A* using only kinematic arguments. If their membership to the GC is confirmed, most of the isolated MSs are likely not associated with either the Arches or Quintuplet clusters or Sgr A*. Only a few MSs have proper motions suggesting they are likely members of the Arches cluster, in agreement with previous spectroscopic results. Line-of-sight radial velocities and distances are required to shed further light on the origin of most of these massive objects. We also present an analysis of other fast-moving objects in the GC region, finding no clear excess of high-velocity escaping stars. We make our astro-photometric catalogs publicly available., Comment: 28 pages, 33 figures, 9 tables. Accepted for publication in MNRAS. [v3: Fixed bibliography]

In the present paper, a procedure is presented for the evaluation of the safety factor and the limit conditions of masonry arches subject to gravity loadings. The proposed procedure can be considered an extension of Heyman’s method for determining the geometrical safety factor. At variance with Heyman’s method, herein, the analysis of the static safety condition for the arch is performed by means of modified kinematic configurations of the arch obtained by encompassing settlements at the arch constraints. Furthermore, the procedure allows the identification of the critical locations of the hinges in the arch at the limit conditions. Moreover, the present procedure allows the determination of the geometrical vertical displacement that the crown of the arch can accommodate at the safety limit conditions. Finally, the proposed procedure is applied to a real case in order to show its effectiveness. Numerical results are reported and commented on in order to clarify the application of the proposed procedure for the definition of the safety factor of the arched structure and the evaluation of the critical geometrical configuration compatible with the limit conditions of the arch.

Scissor mechanisms are used as deployable structures in industrial products, architecture, and aerospace structures. In general, tubular scissor mechanisms (TSMs), composed of scissor-like elements on their surrounding facets, extend collinearly to serve as lifters, masts, and bridges. Furthermore, curved TSMs can form circular arches to serve as spatial frames and space antennas. However, previous studies proposed limited configurations of TSM models and did not present detailed geometrical formulations. This paper presents new compositions of curved TSMs that can extend by winding two-dimensionally or twisting three-dimensionally. Detailed geometrical formulations of the scissor-like elements were analytically derived to generate a variety of extended shapes. In addition to the numerical simulations using 3D CAD, physical models were assembled to verify their deployability considering realistic sizes of bars and joints. This work widens the deployability of extendable scissors mechanisms, which will eventually broaden the usage of this structure in practical applications.

Graphic methods can be used when teaching Building Structures to solve some problems such as analysis of cables and arches through funiculars tracing; analysis of trusses with the Cremona method; graphically obtaining the lateral earth pressure of the ground on a wall and many other problems. This article presents some tools to solve these problems using GeoGebra, a free interactive mathematical software for education created by Markus Hohenwarter. The usefulness of Geogebra in teaching Building Structures will be presented through specifically created resources. These are new resources with approaches and utilities that commercial software does not have either. For each problem studied, the theory on which it is based is shown, the general description of the parameters used in Geogebra, and the application that has been created. In addition, the learning objectives to be achieved and the results docents will be shown

Background: Fingerprints studied by dermatoglyphics are unique for a given individual. It depends on the genetic makeup of an individual. Hypertension, a harbinger of many complications, is determined by genetic and environmental factors. In this observational study, we tried to find an association of palmar dermatoglyphic parameters and hypertension. Method: Two hundred fifty known hypertensives as cases and 250 normotensives as controls were enrolled after considering inclusion and exclusion criteria. Dermatoglyphic patterns on tips of fingers obtained by digital imaging were noted in both the groups, and “atd” angle was calculated using “screen protractor” software. Collected data were statistically analyzed to find any association between dermatoglyphic qualitative and dermatoglyphic quantitative patterns and hypertension. Result: Mean “atd” angle was higher in cases than in controls. Comparison of dermatoglyphic patterns in both the groups in various ways—both hands together, the right hand and left hand separately, similar fingers on right and left hand together, and similar fingers separately—was performed which revealed that at every level, whorls were more frequent in cases than in controls and that distribution of dermatoglyphic patterns were statistically significant in cases than in controls. Conclusion: Fingerprint patterns can be reliably used to identify individuals likely at risk for hypertension, and accordingly, preventive measures can be targeted. This subject area demands a need for further research and analysis with large sample size to allow dermatoglyphics to evolve into a cost-effective and handy tool for identifying individuals at risk of hypertension. Keywords: “atd” angle, Arches, Fingerprints, Loops, Raised blood pressure, Whorls

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Neste trabalho foram abordadas formulações para análise da estabilidade estrutural de arcos simétricos, com forma circular, por meio da determinação da força referente ao primeiro modo de flambagem (força crítica). Quatro condições de carregamento foram propostas para análise: força uniformemente distribuída na direção radial, força verticalmente concentrada no meio do vão, força uniformemente distribuída ao longo do vão e força concentrada na direção radial. Três modelos para análise foram desenvolvidos a partir das formulações, sendo um modelo teórico obtido pela resolução da equação diferencial de deslocamento radial, um modelo matricial de análise por autovalor a partir do Método das Foças Elásticas, e um modelo aproximado usando o Método dos Resíduos Ponderados e o Método de Galerkin. O modelo teórico foi desenvolvido para análise de arcos triarticulados, biarticulados e biengastados, enquanto os demais modelos foram voltados à análise de arcos biarticulados. Para comparação dos resultados foram atribuídos valores para o ângulo de abertura do arco e relação flecha/vão a fim de caracterizar coeficientes de flambagem, e realizada simulação numérica em programa computacional baseado no Método dos Elementos Finitos. Foi constatado que os modelos propostos forneceram resultados similares para a análise de arcos biarticulados, e que a relação flecha/vão próxima de 0,3 possibilita valores elevados para os coeficientes de flambagem segundo as condições de carregamento avaliadas, possibilitando ao arco maior eficiência quanto à estabilidade. Também foi desenvolvido um programa computacional destinado à determinação da força crítica de flambagem em arcos circulares. This research presents formulations for structural stability analysis of symmetrical arches with circular shape by determining the load related to the first buckling mode (critical load). Four loading conditions were suggested for analysis: uniform distributed load in the radial direction, concentrated load vertically in the middle of the span, uniform distributed load in the span direction and radial concentrated load. Three models were formulated for analysis, being a theoretical model obtained from the differential radial displacement equation resolution, a matrix model with eigenvalue analysis obtained from the Elastic Loads Method, and an approximate model using the Weighted Residual Method and the Galerkin Method. The theoretical model was developed for three-hinged, two-hinged, and hingeless arch analysis, while the others models were developed for two-hinged arch analysis only. To compare the results were assigned values for the arch’s opening angle in order to characterize buckling coefficients, and performed numerical simulation with Finite Element Analysis software. The proposed models provide similar results for the analysis of two-hinged arches, and the rise-to-span ratio almost 0.3 allows high values for buckling coefficients evaluated according to the loading conditions, allowing the arch to be more stability efficiently. It also has developed a software, which enables the critical buckling load calculation of circular arches. Dissertação (Mestrado)

We present ARCHes, a fast and accurate haplotype-based approach for inferring an individual’s ancestry composition. Our approach works by modeling haplotype diversity from a large, admixed cohort of hundreds of thousands, then annotating those models with population information from reference panels of known ancestry. The running time of ARCHes does not depend on the size of a reference panel because training and testing are separate processes, and the inferred population-annotated haplotype models can be written to disk and reused to label large test sets in parallel (in our experiments, it averages less than one minute to assign ancestry from 32 populations to 1,001 sections of a genotype using 10 CPU). We test ARCHes on public data from the 1,000 Genomes Project and HGDP as well as simulated examples of known admixture. Our results demonstrate that ARCHes outperforms RFMix at correctly assigning both global and local ancestry at finer population scales regardless of the amount of population admixture.Author SummaryHuman DNA is inherited from ancestors that come from different populations across the globe and across time. Being able to identify which of those populations make up an individual’s DNA, how much they contribute, and on which chromosomes, is currently an important open research problem with many applications in the study of human diversity and history. As DNA sequencing and genotyping technology has developed, we have greater and greater amounts of data, which allows for the development of new sophisticated machine learning methods to approach this problem, and presents a need to process large amounts of data efficiently. These methods learn from examples of DNA data from known populations, and must be robust to differences in size and diversity among those reference populations. We present a new approach to this problem called ARCHes (Ancestry inference usingReference labeledClusters ofHaplotypes), that models the global diversity of small segments of human DNA sequence (“haplotypes”), and the extent to which these haplotypes are associated with each of a set of population reference panels. It then computes the most likely population assignments and the points along the genome where the populations change. Our experiments show that ARCHes has superior accuracy compared to a state-of-the-art method in identifying source populations and their locations on the genome, regardless of the number of different populations present in the genome, how closely related those populations are. ARCHes is also able to model populations despite having a small amount of population reference DNA data.

The management and presentation of cultural heritage over a given region requires a dedicated database which can store all relevant information (location, text, photography, 3D models, animations etc.) and an intuitive way of accessing this information (searching via different criteria such as geo-location, time-frame, type of find, state of preservation, etc.). We decided to test a recently available open source platform, Arches 3.0, to construct a database of all known logboats and other early watercraft in the country of Slovenia: the Early Watercraft Database. The software platforms of existing inventories are mostly proprietary, expensive to maintain and difficult to interconnect and upgrade to new requirements. Existing database inventories are therefore difficult to combine and this makes the study of early watercraft finds on a global scale, independent of modern state boundaries, more difficult. By contrast, information stored in applications developed on the Arches platform can be easily merged. The Early Watercraft Database application demonstrates the ability of the Arches platform to be employed for a wide range of applications; it can be used for small-scale solutions but it can also be extended to accommodate large-scale (global) inventory requirements. The Arches open source heritage inventory and management system is sponsored by the Getty Conservation Institute and the World Monuments Fund.

Terrestrial laser scanning (TLS) is capable to be a reliable deformation monitoring device with high-precision for concrete composite structures. Measurements based on TLS for an arch structure with monotonic loading is carried out. In this paper, comparison between original and optimized extraction of point clouds are presented. Surface approximation is implemented, where the vacant measurement area is also covered and the uncertainties of different-order surfaces are investigated. The results of surface approximation based on TLS measurement have certain relation with surface roughness of specimen, which will be eliminated by subtraction in deformation calculation. DFG Natural Science Foundation of Jiangsu Province

Indian woman since ancient days had played an important role in the socio-cultural and philosophical development of the country. Especially in Medieval India, the royal ladies of the Mughal court were almost as remarkable as their male counterparts. Royal Mughal ladies like Hamida Banu Begam, Haji Begam, Nurjahan Begam, Jahanara Begam, Roshanara Begam, Zeb-un-Nisa Begum etc. not only played a dominant role in contemporary politics but also contributed a lot to artistic field. The present article is an attempt to highlight the contribution of Royal Mughal ladies especially in Artistic field.

The present paper discusses simple compatibility, equilibrium, and constitutive equations for a non-prismatic planar beam. Specifically, the proposed model is based on standard Timoshenko kinematics (i.e., planar cross-section remain planar in consequence of a deformation, but can rotate with respect to the beam center-line). An initial discussion of a 2D elastic problem highlights that the boundary equilibrium deeply influences the cross-section stress distribution and all unknown fields are represented with respect to global Cartesian coordinates. A simple beam model (i.e. a set of Ordinary Differential Equations (ODEs)) is derived, describing accurately the effects of non-prismatic geometry on the beam behavior and motivating equation’s terms with both physical and mathematical arguments. Finally, several analytical and numerical solutions are compared with results existing in literature. The main conclusions can be summarized as follows. (i) The stress distribution within the cross-section is not trivial as in prismatic beams, in particular the shear stress distribution depends on all generalized stresses and on the beam geometry. (ii) The derivation of simplified constitutive relations highlights a strong dependence of each generalized deformation on all the generalized stresses. (iii) Axial and shear-bending problems are strictly coupled. (iv) The beam model is naturally expressed as an explicit system of six first order ODEs. (v) The ODEs solution can be obtained through the iterative integration of the right hand side term of each equation. (vi) The proposed simple model predicts the real behavior of non-prismatic beams with a good accuracy, reasonable for the most of practical applications.

The advanced technology of the new photogrammetric systems, whose progressive improvements could be due to both better resolution of the new cameras and the recent development of sophisticated interpolation algorithms, permits nowadays register not only the general aspect of the building architecture plan and elevations but also, learning in detail the geometry of the parts that integrate the building, and more significantly, the main elements of its structure. In fact, it has a great interest in many areas, and specially in masonry structures, where stability analysis require detailed information about the structural joints of the materials that set the element as well as the specific geometry of the junction that appears between the contact of one block with another. In this work, we demonstrate that a complex photogrammetry technique can be used as a geometric base to analyze masonry structures. The San Millan de Segovia's church is used as an example of structure for the study. This study addresses the different parts of the process, from the photogrammetric lifting to the simplification processes used for implementing this procedure automatically to any type of structure, pointing out the operational simplicity that this technique allows.ResumenLa precisión de los nuevos sistemas de registro fotogramétrico, cuya progresiva mejora puede atribuirse tanto a la elevada resolución de las cámaras modernas como al reciente desarrollo de sofisticados algoritmos de interpolación, permite en la actualidad registrar no solamente las trazas generales de la planta y los alzados de un edificio sino, además, conocer en detalle la geometría de las piezas que lo componen, y muy señaladamente de los elementos que forman su estructura. Este hecho es de gran interés en muchos campos, y especialmente en el ámbito de las estructuras de fábrica, ya que los análisis de estabilidad de éstas precisan (al menos cuando se pretende incorporar al estudio el comportamiento local) de información detallada sobre la articulación de los materiales que las componen: trabas, aparejos o geometrías específicas de los lechos en los que unas piezas entran en contacto con otras. El presente trabajo desarrolla un caso concreto, el de la iglesia de San Millán de Segovia, un edificio en el que el levantamiento fotogramétrico complejo se ha empleado como base geométrica para el análisis de la estructura de fábrica. En este estudio se desarrollan las distintas fases del proceso, desde el levantamiento hasta los procesos de simplificación geométrica necesarios para poder implementar cualquier tipo de análisis estructural de forma automática, poniendo el énfasis en las facilidades operativas que posibilita esta técnica. AbstractThe advanced technology of the new photogrammetric systems, whose progressive improvements could be due to both better resolution of the new cameras and the recent development of sophisticated interpolation algorithms, permits nowadays register not only the general aspect of the building architecture plan and elevations but also, learning in detail the geometry of the parts that integrate the building, and more significantly, the main elements of its structure. In fact, it has a great interest in many areas, and specially in masonry structures, where stability analysis require detailed information about the structural joints of the materials that set the element as well as the specific geometry of the junction that appears between the contact of one block with another. In this work, we demonstrate that a complex photogrammetry technique can be used as a geometric base to analyze masonry structures. The San Millan de Segovia's church is used as an example of structure for the study. This study addresses the different parts of the process, from the photogrammetric lifting to the simplification processes used for implementing this procedure automatically to any type of structure, pointing out the operational simplicity that this technique allows.ResumenLa precisión de los nuevos sistemas de registro fotogramétrico, cuya progresiva mejora puede atribuirse tanto a la elevada resolución de las cámaras modernas como al reciente desarrollo de sofisticados algoritmos de interpolación, permite en la actualidad registrar no solamente las trazas generales de la planta y los alzados de un edificio sino, además, conocer en detalle la geometría de las piezas que lo componen, y muy señaladamente de los elementos que forman su estructura. Este hecho es de gran interés en muchos campos, y especialmente en el ámbito de las estructuras de fábrica, ya que los análisis de estabilidad de éstas precisan (al menos cuando se pretende incorporar al estudio el comportamiento local) de información detallada sobre la articulación de los materiales que las componen: trabas, aparejos o geometrías específicas de los lechos en los que unas piezas entran en contacto con otras. El presente trabajo desarrolla un caso concreto, el de la iglesia de San Millán de Segovia, un edificio en el que el levantamiento fotogramétrico complejo se ha empleado como base geométrica para el análisis de la estructura de fábrica. En este estudio se desarrollan las distintas fases del proceso, desde el levantamiento hasta los procesos de simplificación geométrica necesarios para poder implementar cualquier tipo de análisis estructural de forma automática, poniendo el énfasis en las facilidades operativas que posibilita esta técnica.

In this paper a procedure for the dynamic identification of damage in spatial Timoshenko arches is presented. The proposed approach is based on the calculation of an arbitrary number of exact eigen-properties of a damaged spatial arch by means of the Wittrick and Williams algorithm. The proposed damage model considers a reduction of the volume in a part of the arch, and is therefore suitable, differently than what is commonly proposed in the main part of the dedicated literature, not only for concentrated cracks but also for diffused damaged zones which may involve a loss of mass. Different damage scenarios can be taken into account with variable location, intensity and extension of the damage as well as number of damaged segments. An optimization procedure, aiming at identifying which damage configuration minimizes the difference between its eigen-properties and a set of measured modal quantities for the structure, is implemented making use of genetic algorithms. In this context, an initial random population of chromosomes, representing different damage distributions along the arch, is forced to evolve towards the fittest solution. Several applications with different, single or multiple, damaged zones and boundary conditions confirm the validity and the applicability of the proposed procedure even in presence of instrumental errors on the measured data., Comment: 34 pages, 19 figures

Facial form depends on the precise positioning of cartilage, bone, and tooth fields in the embryonic pharyngeal arches. How complex signaling information is integrated to specify these cell types remains a mystery. We find that modular expression of Forkhead-domain transcription factors (Fox) in the zebrafish face arises through integration of Hh, Fgf, Bmp, Edn1, and Jagged-Notch pathways. Whereas loss of C-class Fox proteins results in reduced upper facial cartilages, loss of F-class Fox proteins results in distal jaw truncations and absent midline cartilages and teeth. We show that Fox proteins are required for Sox9a to promote chondrogenic gene expression. Fox proteins are sufficient in neural crest-derived cells for cartilage development, and neural crest-specific misexpression of Fox proteins expands the cartilage domain while inhibiting bone. These results support a modular role for Fox proteins in establishing the competency of progenitors to form cartilage and teeth in the face.

In this work, the seismic capacity of single and multi-span masonry arch bridges was assessed by limit analysis. A preliminary statistical survey was carried out on a stock of about 750 railway bridges in Italy, classified according to characteristics and expected collapse mechanisms under seismic excitation. A comprehensive parametric study was carried out on identified homogeneous classes, to calculate limit horizontal accelerations triggering the collapse mechanism in longitudinal and transverse directions. Iso-acceleration envelope curves, representing limit horizontal acceleration of the bridge as a function of geometric parameters, were then derived. These graphs can be used for preliminary seismic safety checking of existing masonry bridges, once the main geometric parameters are available by simple visual inspections and geometric surveys, and can easily be implemented in a Bridge Management System to prioritise seismic retrofitting interventions.

Within this paper, an analytical formulation is provided and used to determine the natural frequencies and mode shapes of a planar beam with initial pre-stress and large variable curvature. The static configuration, mode shapes, and natural frequencies of the pre-stressed beam are obtained by using geometrically exact, Euler–Bernoulli beam theory. The beam is assumed to be not shear deformable and inextensible because of its slenderness and uniform, closed cross-section, as well as the boundary conditions under consideration. The static configuration and the modal information are validated with experimental data and compared to results obtained from nonlinear finite-element analysis software. In addition to the modal analysis about general static configurations, special consideration is given to an initially straight beam that is deformed into semi-circular and circular static configurations. For these special circular cases, the partial differential equation of motion is reduced to a sixth-order differential equation with constant coefficients, and solutions of this system are examined. This work can serve as a basis for studying slender structures with large curvatures.

This paper presents the development of a three dimensional computational model, based on the Discrete Element Method (DEM), which was used to investigate the effect of the angle of skew on the load carrying capacity of twenty-eight different in geometry single span stone masonry arches. Each stone of the arch was represented as a distinct block. Mortar joints were modelled as zero thickness interfaces which can open and close depending on the magnitude and direction of the stresses applied to them. The variables investigated were the arch span, the span : rise ratio and the skew angle. At each arch, a full width vertical line load was applied incrementally to the extrados at quarter span until collapse. At each load increment, the crack development and vertical deflection profile was recorded. The results compared with similar “square” (or regular) arches. From the results analysis, it was found that an increase in the angle of skew will increase the twisting behaviour of the arch and will eventually cause failure to occur at a lower load. Also, the effect of the angle of skew on the ultimate load that the masonry arch can carry is more significant for segmental arches than circular one.

Digital libraries have become an excellent information resource for researchers. However, users of digital libraries would be served better by having the relevant items ‘pushed’ to them. In this research, we present various automatic recommendation systems to be used in a digital library of Serbian PhD Dissertations. We experiment with the use of Latent Semantic Analysis (LSA) in both content and collaborative recommendation approaches, and evaluate the use of different similarity functions. We find that the best results are obtained when using a collaborative approach that utilises LSA and Pearson similarity. © Springer International Publishing AG 2017. 10151 LNCS 100 111 Sponsors: European Cooperation in Science and Technology Conference code: 189199

While the Web of (entity-centric) data has seen tremendous growth over the past years, take-up and re-use is still limited. Data vary heavily with respect to their scale, quality, coverage or dynamics, what poses challenges for tasks such as entity retrieval or search. This chapter provides an overview of approaches to deal with the increasing heterogeneity of Web data. On the one hand, recommendation, linking, profiling and retrieval can provide efficient means to enable discovery and search of entity-centric data, specifically when dealing with traditional knowledge graphs and linked data. On the other hand, embedded markup such as Microdata and RDFa has emerged a novel, Web-scale source of entitycentric knowledge. While markup has seen increasing adoption over the last few years, driven by initiatives such as schema.org, it constitutes an increasingly important source of entity-centric data on the Web, being in the same order of magnitude as the Web itself with regards to dynamics and scale. To this end, markup data lends itself as a data source for aiding tasks such as knowledge base augmentation, where data fusion techniques are required to address the inherent characteristics of markup data, such as its redundancy, heterogeneity and lack of links. Future directions are concerned with the exploitation of the complementary nature of markup data and traditional knowledge graphs. The final publication is available at Springer via http://dx.doi.org/ 10.1007/978-3-319-53640-8_1.

A new approach toward a fully computer-aided design (CAD) integrated structural analysis of arched masonry structures is proposed and a new MATLAB-based computational tool, named ArchNURBS,...

Die heterogene Natur archäologischer Daten wird bis heute meist in relationalen Datenbanken abgebildet. Datenmodellierungen mit NoSQL-Datenbanken oder in Graphen, fristen auch im Jahr 2015 noch ein Nischendasein, obwohl die konzeptionellen wie auch die technischen Grundlagen seit langem zur Verfügung stehen und einen Zugang in das Web 3.0 und in die Linked Data Cloud ermöglichen. Das i3mainz (Institut für Raumbezogene Informations- und Messtechnik) arbeitet in verschiedenen Projekten mit interdisziplinären Kontexten an Graphenstrukturen, insbesondere auch an der Modellierung jener mit Hilfe des W3C-standardisierten Resource Description Framework (RDF). Ein besonderes Augenmerk liegt dabei bei der Evaluation von Methoden zur standardisierten und interoperablen Vorhaltung komplexer archäologischer Fundstellendaten. Die technische Basis bildet dabei das auf dem CIDOC Conceptual Reference Model (CIDOC CRM) und Simple Knowledge Organization System (SKOS) basierende ARCHES Heritage & Management System. Die von Kooperationspartnern innerhalb des Mainzer Zentrum für Digitalität in den Geistes- und Kulturwissenschaften»mainzed« in unterschiedlicher Form zur Verfügung gestellten archäologischen Fachdatenkönnen für eine Vielzahl von Szenarien als exemplarisch angesehen werden. Ziele der Initiative sind die standardisierte und interoperable Vorhaltung strukturiert modellierter archäologischer Datensätze. Dabei steht die Abbildung möglichst vieler Prozesse wie etwa Abfrage, Pflege, Erweiterung und Analyse im Mittelpunkt, welche auch von nicht direkt im Projekt involvierten Wissenschaftlern erbracht werden sollen. Das Paper präsentiert technische Grundlagen semantischer Datenmodellierung unter Verwendung von CIDOC CRM. Weiterhin werden prototypische Fragestellungen behandelt: Welche Voraussetzungen sollten Daten hinsichtlich Aufbau und Struktur erfüllen? Welche Schritte sind zur Datenintegration in vorhandene Graphenstrukturen nötig? Wie können diese Strukturen erweitert und auf individuelle Bedürfnisse angepasst werden? Welche prototypischen Probleme wurden dabei identifiziert? Welchen Vorteil bieten interaktive Web-Tools zur Erstellung von Thesauri (Authority Files) als Linked Open Data wie z.B. der Reference Data Manager oder das Labeling Systemgegenüber herkömmlich verwendeter, nicht HTTP-adressierbarer und nicht zitierbarer kontrollierter Vokabulare? Abschließend wird diskutiert, inwiefern CIDOC CRM modellierte Daten überhaupt geeignet sein können, eine Basis für interoperable Systeme darzustellen. Ist die CIDOC CRM inhärente Komplexität nicht gerade deswegen als problematisch zu bezeichnen? Können auf Triple basierende Modellierungen ein gleichwertiger Ersatz für auf Tupel (relationale Datenbanken) basierende Datenstrukturen darstellen oder sogar einen Mehrwert bezüglich bislang unbeantworteter Fragestellungen bilden? Welche Vorteile für den wissenschaftlichen Diskurs sind kurz- und langfristig zu erwarten?

Magistrska naloga se loteva problema evidence in predstavitve nepremične kulturne dediščine s pomočjo odprtokodne platforme Arches. Dosedanji registri so v večini narejeni z različnimi zaprtimi orodji, zaradi česar je razvoj takšnih sistemov ustrezno dražji, predvsem pa so takšni sistemi zaradi svoje zaprtosti med seboj nepovezljivi. Platforma Arches naslavlja in rešuje velik del teh problemov. V okviru magistrske naloge sem prilagodil sistem evidenci in predstavitvi izuma in razvoja zgodnjih plovil (EarlyWatercraft.org) in z njim predstavil vse do sedaj evidentirane slovenske deblake. Sistem služi predvsem za predstavitev koncepta rešitve, ki ga je mogoče enostavno razširiti za uporabo na širšem področju (tudi po vsem svetu) ali pa ga prilagoditi uporabi tako ožje kot širše usmerjenim registrom. Izdelek je dobrodošla pridobitev za predstavitev tega področja z najnovejšimi tehnologijami in standardi, ki jih nudi sistem Arches. This master thesis addresses the challenges associated with the management and presentation of immovable cultural heritage using the Arches open source platform. The existing inventories are mostly proprietary, expensive and extremely difficult to interconnect. The Arches platform comes to rescue with all of that. In my thesis, Arches has been employed to present the invention and development of early watercraft, and includes a database of all known logboats in the territory of Slovenia. The EarlyWatercraft.org application demonstrates the ability of the Arches platform to be employed in a wide range of uses it can be applied for small-scale solutions but it can also be extended to accomodate large-scale (global) inventory requirements. The product presents early watercraft, which is a less known area of cultural heritage, to a wider audience using modern technologies and standards.

Earthquakes represent one of the major threats to the stability of the world architectural heritage, which is mostly constituted by unreinforced masonry (URM) structures. The dynamic behavior of these structures is complex and highly non-linear, as it involves sliding and rocking of the component blocks. As a result, numerical modeling seems to be the most appropriate predictive approach and, in particular, the Discrete Element Method (DEM) has recently emerged as a very promising tool for this purpose. Although multi-drum columns and arches on buttresses are typical components of historic URM structures, their modeling with the DEM has been the subject of relatively limited research. Moreover, a set of input parameters is required for the definition of the numerical model and, due to the uncertainty and difficulty in their experimental evaluation, these parameters are usually set in an arbitrary way. In this paper, a systematic parametric study based on the DEM is adopted to evaluate the dynamic behavior and resistance of multi-drum columns and arches on buttresses subjected to two different base motions, i.e. step and harmonic impulses. A detailed investigation on failure domains and modes of collapse is presented. The main features of the dynamic response of masonry structures and the sensitivity of the response to changes in the excitation, geometry and mechanical parameters are discussed.

The present paper deals with the identification of a concentrated damage in an elastic parabolic arch through the minimization of an objective function which measures the differences between numerical and experimental values of static displacements. The damage consists in a notch that reduces the height of the cross section at a given abscissa and therefore causes a variation in the flexural stiffness of the structure. The analytical values of static displacements due to applied loads are calculated by means of the principle of virtual work for both the undamaged and damaged arch. First, pseudo-experimental data are used to study the inverse problem and investigate whether a unique solution can occur or not. Various damage intensities are considered to assess the reliability of the identification procedure. Then, the identification procedure is applied to an experimental case, where displacements are measured on a prototype arch. The identified values of damage parameters, i.e., location and intensity, are compared to those obtained by means of a dynamic identification technique performed on the same structure.

The paper presents the designing and research works of Professor Anatolijus Rozenbliumas. The Professor was one of the most outstanding Lithuanian engineers and one of the most important scientists in the building field. He created an original theory of calculating the reinforced concrete deformation. The theory was recognized by the most outstanding specialists in this field. Article in English

The Tanaro Bridge, an 18 span masonry bridge built in 1866, has been investigated both in service conditions and at different stages of its demolition. A comparative characterization of the brickwork was performed by means of compressive tests on cylinders, flat jacks, sonic and sclerometer tests, while the natural frequencies and mode shapes of the bridge and the brickwork damping have been identified by dynamic tests on the bridge. Data from material testing were used to set up FEM models, so that the reliability of the material characterization procedures is demonstrated by comparison between the dynamic tests and FEM results. A rational comparative analysis of the results showed that: (i) a large part of the bridge needs to be monitored if the mode shapes are to be identified through dynamic tests; (ii) elastic FEM models can provide some information on the bridge response under service loads provided the mechanical parameters are adequately identified. Besides, some information has been deduced on the effectiveness, in service conditions, of some retrofitting technique: (i) transversal tie bars through the arch thickness have been proved almost ineffective; (ii) internal spandrels were found to be quite efficient in connecting adjacent spans.

The aim of this paper is to define an exact formulation of a curved beam finite element for static analysis. The basic equations are combined in the coupled fundamental system in terms of radial displacement v , tangential displacement u and rotation ϕ . An original procedure for solving the fundamental system of equations is used. A finite element formulation based on shape functions that satisfy the homogeneous form of the fundamental system of differential equations is developed. The effects of bending moment, axial extension and transverse shear are taken into account. The exact elastic solution renders the element obtained free of shear and membrane locking. An efficient numerical procedure is presented for determining the pressure curve in the case of circular arches under static loading and arbitrary bonding conditions. The solution obtained is applicable to the analysis of both thin and thick curved beams. Several examples of arches with various loading and boundary conditions are investigated to illustrate the validity and the accuracy of the method. Finally, the effect of the arch rise on the structural response is pointed out.

Arches are often supported elastically by other structural members. This paper investigates the in-plane nonlinear elastic behaviour and stability of elastically supported shallow circular arches that are subjected to a radial load uniformly distributed around the arch axis. Analytical solutions for the nonlinear behaviour and for the nonlinear buckling load are obtained for shallow arches with equal or unequal elastic supports. It is found that the flexibility of the elastic supports and the shallowness of the arch play important roles in the nonlinear structural response of the arch. The limiting shallownesses that distinguish between the buckling modes are obtained and the relationship of the limiting shallowness with the flexibility of the elastic supports is established, and the critical flexibility of the elastic radial supports is derived. An arch with equal elastic radial supports whose flexibility is larger than the critical value becomes an elastically supported beam curved in elevation, while an arch with one rigid and one elastic radial support whose flexibility is larger than the critical value still behaves as an arch when its shallowness is higher than a limiting shallowness. Comparisons with finite element results demonstrate that the analytical solutions and the values of the critical flexibility of the elastic supports and the limiting shallowness of the arch are valid.

This chapter is a critical presentation of studies over the last 10 years on the mechanical response of masonry arches and vaults. More precisely, we focus on a study of masonry arches conducted in parallel via both nonlinear elastic and limit analyses. The one-dimensional elastic model for masonry arches incorporates a simple but effective nonlinear constitutive law. In turn, collapse analysis is performed by the so-called ‘method of stability areas’, originally proposed by Durand-Claye in 1867. Rather than offering two alternative paths, the approaches may be considered complementary points of view on the same problem. A reasoned illustration of the concepts in question is furnished by the topics addressed: an analysis of the possible failure mechanisms of a pointed arch subject to its own weight; the search for explicit solutions to the equilibrium problem of a depressed arch subject to a uniformly distributed load; the study of arches of different shapes subject to their own weight and the weight of a superimposed wall.

In the 17th century the town of Chioggia, located in the Italian Venetian Lagoon, was connected to the mainland by an unreinforced masonry bridge called Ponte Lungo (long bridge) composed of an elegant sequence of masonry arches. The bridge withstood the many vicissitudes that this part of Italy lived through as well as the increase in static and dynamic loads brought by the 20th century. However, excessively heavy reinforced concrete additions made in the 1950s to accommodate both motorized vehicles and pedestrians quickly deteriorated by concrete spalling and rebar corrosion because of inadequate design and the aggressive environment, and the additions could not provide for the ongoing increases in needed capacity. This paper describes the design and construction of the recent Ponte Lungo renovation, which is part of a massive safeguarding effort for the Venetian Lagoon carried out by the Italian Ministry of Infrastructure and Transport together with the Venice Water Authority via the Consorzio Venezia ...

Esse trabalho fornece algumas formulações de elementos finitos circulares para análise de arcos e anéis. Atenção especial é dada ao cálculo da matriz de rigidez dos elementos finitos desenvolvidos, onde os efeitos das deformações de flexão, cisalhantes e de membrana são levados em consideração. O acoplamento desses efeitos permite a análise do comportamento de arcos esbeltos e espessos. No final do artigo, através da análise de problemas estruturais encontrados na literatura, pretende-se verificar a eficiência das formulações implementadas. O objetivo é conhecer a melhor modelagem numérica para obtenção dos deslocamentos e forças resultantes de sistemas estruturais curvos. A study of curved beam element formulations for arch and ring models is presented in this paper. Flexural, axial and shear deformation effect is all taken into account as derivations of the beam element stiffness matrices. They contain the coupled influences of shear and membrane locking effects. At the end of this paper, using numerical and analytical responses to the structural problems found in literature, the formulation efficiency verifies. So, the best numerical models are found and the displacements and resultant forces are obtained for the thin and thick curved structural systems.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:29:00Z No. of bitstreams: 0 Made available in DSpace on 2014-05-27T11:29:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-04-26 A finite element analysis was used to compare the effect of different designs of implant-retained overdentures and fixed full-arch implant-supported prosthesis on stress distribution in edentulous mandible. Four models of an human mandible were constructed. In the OR (O'ring) group, the mandible was restored with an overdenture retained by four unsplinted implants with O'ring attachment; in the BC (bar-clip) -C and BC groups, the mandibles were restored with overdentures retained by four splinted implants with bar-clip anchor associated or not with two distally placed cantilevers, respectively; in the FD (fixed denture) group, the mandible was restored with a fixed full-arch four-implant-supported prosthesis. Models were supported by the masticatory muscles and temporomandibular joints. A 100-N oblique load was applied on the left first molar. Von Mises (σvM), maximum (σmax) and minimum (σmin) principal stresses (in MPa) analyses were obtained. BC-C group exhibited the highest stress values (σvM=398.8, σmax=580.5 and σmin=-455.2) while FD group showed the lowest one (σvM=128.9, σmax=185.9 and σmin=-172.1). Within overdenture groups, the use of unsplinted implants reduced the stress level in the implant/prosthetic components (59.4% for σvM, 66.2% for σmax and 57.7% for σmin versus BC-C group) and supporting tissues (maximum stress reduction of 72% and 79.5% for σmax, and 15.7% and 85.7% for σmin on the cortical and trabecular bones, respectively). Cortical bone exhibited greater stress concentration than the trabecular bone for all groups. The use of fixed implant dentures and removable dentures retained by unsplinted implants to rehabilitate edentulous mandible reduced the stresses in the periimplant bone tissue, mucosa and implant/prosthetic components. © 2013 Elsevier Ltd. Department of Dental Materials and Prosthodontics Araçatuba Dental School Univ Estadual Paulista (UNESP), Sao Paulo Smarttech Company, Sao Paulo Department of Prosthodontics and Periodontology Piracicaba Dental School State Univ of Campinas (UNICAMP), Sao Paulo Department of Dental Materials and Prosthodontics Araçatuba Dental School Univ Estadual Paulista (UNESP), Sao Paulo

In this work limit analysis theorems are exposed in order to study their appliance to the analysis of masonry arches. All this allows studying the role of lines of thrust and curves of pressure on the safety of arches. En este trabajo se enuncian los teoremas de rotura y sus corolarios para aplicarlos al cálculo en rotura de arcos. Después de analizar la teoría de arcos, se estudia el significado de la línea de presiones y de la línea de empujes desde el punto de vista del cálculo a rotura.

Reasons are studied for the short life of sprung-suspended roofs of open-hearth furnaces and refractory objects are developed with reduced thermal conductivity and a special hook. During refractory laying a shrinkage-free high-temperature laying mortar is used. OAO Nizhnyi Tagil' Metallurgical Combine organizes industrial output of the refractories developed. Industrial testing is carried out in open-hearth furnace arched roofs of OAO Nizhnyi Tagil' Metallurgical Combine (NTMK) and ZAO Nizhnyi Sergi Metalware and Metallurgical Plant (NMMZ). According to test results the increase in roof life is 20 - 30%, and the economic effect for two open-hearth furnaces is 4,656 million rubles per year. © 2013 Springer Science+Business Media New York.

This paper presents the constructive development of a medieval bridge using almost exclusively the stratigraphic method to analyze the subsoil and the standing structure. This work has enabled recording the interaction between the bridge and the river, including successive destructions and rebuildings of the bridge and their consecutive improvements. El artículo aborda el estudio de la evolución constructiva de un puente de origen medieval, utilizando casi exclusivamente el método estratigráfico tanto en el análisis del subsuelo como en los paramentos de la estructura. El estudio ha permitido documentar la interacción entre el puente y el río con las sucesivas destrucciones y recomposiciones de la estructura, así como las mejoras que cada reparación aportaba respecto de la situación anterior.

Avui dia cal destacar els arcs i voltes com a tecnologia estructural de baix cost econòmic i ambiental, i que pot facilitar la resolució de cobertes sense un ús excessiu d’acer. La seva durabilitat, versatilitat i senzillesa donen fe d’una saviesa tradicional que va ser abandonada injustificadament i que cal recuperar i actualitzar com a nova via sostenible d’edificar. Aquest article dóna informació i eines de treball basades en l’experiència pròpia de construir i investigar en noves tecnologies més ecològiques durant els darrers vint anys, recuperant alhora un patrimoni tecnològic herència directa d’arquitectes com Ignasi Bosch o Gaudí, del modernisme en general, del gòtic, del romànic i en definitiva de tota relectura de les formes que treballen a compressió modelades per la mateixa natura. Es descriuen diferents tipus de voltes segons el sistema constructiu utilitzat

In the present paper the contributions of Carlos Fernández Casado to Structural Analysis are reviewed. After a description of the international context he was working in, his contributions and their relation to the academic training he received at the Civil Engineering Scholl in Madrid are described. Finally the most interesting aspects of his written work are commented. En este artículo se analizan las aportaciones de Carlos Fernández Casado al cálculo de estructuras. Tras exponer el contexto internacional, se describen sus contribuciones y su relación con la formación que recibió en la Escuela de Ingenieros de Caminos de Madrid. Se finaliza indicando algunos de los méritos más interesantes de su obra escrita.

The study focuses on the arches of the domed halls erected during the Saldjukid period inside of the big mosques, in the part reserved to the sovereign’s use. The author analyses the methods and technics used to trace and build these arches which reveal a great mastery of applied mathematics on the part of the architects and which, beyond their function, possess a distinguished decorative value., Laleh Haeedeh. Les arcs brisés persans : remarques sur leurs particularités géométriques et techniques. In: Histoire de l'art, N°11, 1990. Varia. pp. 3-13.

This thesis investigates the effects of elastic restraint at the supports on the behaviour of shallow concrete arches, and the time-dependent effects of shrinkage and creep of concrete on the nonlinear behaviour of shallow arches. The nonlinear behaviour of shallow circular arches with elastic rotational restraints at each support and subjected to a uniformly distributed radial load is firstly investigated. A virtual work formulation is used to establish both the nonlinear equilibrium equations and the buckling equilibrium equation for shallow arches. The analytical results show that the effects of the stiffness of the rotational restraints on the prebuckling and buckling response are significant. An analytical model is developed for the in-plane elastic stability analysis of shallow parabolic arches with horizontal spring supports subjected to a uniformly distributed vertical load. A parametric study is undertaken using the proposed analytical model. It is found that the effects of the stiffness of the horizontal springs on the prebuckling response, buckling load and buckling behaviour of arches are significant. An analytical model is developed to simulate the time-dependent behaviour of shallow concrete parabolic arches with horizontal spring supports subjected to a sustained loading, and in particular to investigate creep buckling. The time-dependent buckling load and the critical time (or age) of the arches are calculated by using an iterative process based on the proposed model. A systematic parametric study is undertaken, and the results show that the various parameters have a profound effect on the time-dependent buckling load and the prebuckling life of arches. Both short-term and long-term experimental investigations of shallow parabolic tied concrete arches are described and used to validate the analytical models. For the short-term tests, three concrete arches were subjected to a uniformly distributed vertical load and were loaded to failure. For the long-term tests, seven concrete arches were subjected to sustained service loads. The instantaneous and time-dependent deflections were recorded throughout the period of loading, together with the distribution of the horizontal thrust at the supports. Comparisons between the experimental results and the analytical predictions using the analytical models are made to verify the accuracy of the theoretical models.

We propose an alternative approach to count the microscopic static configurations of granular packs under gravity by considering arches. This strategy obviates the problem of filtering out configurations that are not mechanically stable, opening the way for a range of granular models to be studied via ensemble theory. Following this arch-based approach, we have obtained the exact density of states for a 2D, non-interacting rigid arch model of granular assemblies. The calculated arch size distribution and volume fluctuations show qualitative agreement with realistic simulations of tapped granular beds. We have also validated our calculations by comparing them with the analytic solution for the limiting case of a quasi-1D column of frictionless disks. Fil: Slobinsky, Demian Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Tecnológica Nacional. Facultad Regional La Plata. Departamento de Ingeniería Mecánica; Argentina Fil: Pugnaloni, Luis Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Tecnológica Nacional. Facultad Regional La Plata. Departamento de Ingeniería Mecánica; Argentina

A los ojos de un arquitecto del siglo XXI, no es fácil comprender la enorme importancia que se concede a la traza de cantería en el Renacimiento y el Barroco español y francés. Estos trazados de piezas singulares de cantería se realizaban con la finalidad principal de obtener las plantillas de intradós y lecho de las dovelas del elemento que el cantero quiere construir. En el caso de los muros, los arcos de medio punto o escarzanos y las bóvedas de cañón o rebajadas, este problema es elemental. Ahora bien, este saber olvidado es necesario para construir una fábrica de piedra medianamente compleja: cualquiera que incluya lunetos, bóvedas de arista, de naranja, vaídas u ovales, o escaleras de cualquier tipo, desde los humildes husillos ocultos en los contrafuertes de las catedrales hasta las escaleras imperiales de los palacios españoles. Y al contrario de lo que ocurre en Italia, la arquitectura pétrea es la arquitectura por excelencia del Renacimiento español y francés; de ahí la importancia que se concede este saber desde la Edad Media a la ilustración. Este capítulo pasa revista a los puntos esenciales de esta técnica, tratando en primer lugar de los procedimientos de trazado y labra y pasando a continuación a exponer los métodos geométricos que permiten asegurar el control formal de arcos, trompas, decendas de cava, capialzados, escaleras, caracoles y bóvedas. Colegio Oficial de Arquitectos de Murcia

The Colorado Canyons National Conservation Area (CCNCA) is located about 7 miles west of Grand Junction, Colorado. The CCNCA includes rolling saltbush-covered hills, pinyon-junpier and sagebrush-covered mesas, a 24-mile corridor along the Colorado River through Horsethief and Ruby Canyons, and over 70,000 acres of sheer-sided, red-rock canyons, natural arches, caves and alcoves. The 75,550-acre Black Ridge Canyons Wilderness comprises the heart of the CCNCA, with another 5,200 acres stretching into Utah. The CCNCA was given a high priority for land health assessment, a valuable tool in developing the CCNCA Resource Management Plan (RMP).

This Water Resources Management Plan describes the water resources of Arches and Canyonlands National Parks and the issues affecting them. This plan provides detailed descriptions of the hydrologic environment in both parks, discussion of management issues developed in two scoping sessions, and management directives in the form of project statements. Typically, a Water Resources Management Plan is preceded by a scoping meeting held at the park. In this case, the Southeast Utah Group of parks (Southeast Utah Group), which includes Arches National Park, Canyonlands National Park, and Natural Bridges National Monument, held two scoping meetings. The first scoping session, held in May 1996, resulted in the Canyonlands National Park, Arches National Park, and Natural Bridges National Monument Water Resources Scoping Report (Berghoff and Vana-Miller, 1997), and the second scoping meeting, held in September 1997, involved federal, state, and local agencies which helped to refine further the issues developed in the scoping report.