A Constructive Genetic Algorithm for Discrete Dispersion on Point Feature Cartographic Label Placement Problems

This article concerns the point feature cartographic label placement (PFCLP) problem, which is a NP‐hard (Non‐deterministic Polynomial‐time hard) combinatorial problem. It is considered that when all points must be labeled and overlaps are inevitable, the map can be more readable if overlapping labels are placed in a dispersive way, that is, overlapping labels are distant from each other. This work presents a constructive genetic algorithm (CGA) for the discrete dispersion PFCLP that utilizes the notion of masking to preserve optimal subsequences in chromosomes. We also define the discrete dispersion PFCLP as a mixed integer linear programming model, considering the problem of the minimum number of labels in conflict as well. The computational results validate our CGA approach using instances up to 5,046 points.     

Rubble Stone Masonry Walls Strengthened by Three-Dimensional Steel Ties and Textile-Reinforced Mortar Render,Under Compression and Shear Loads

This article addresses the results of a structural strengthening solution for rubble stone masonry walls. The strengthening includes inserting three-dimensional steel ties across the thickness of the walls and a 30-mm layer of air-lime and cement mortar render reinforced with glass fiber mesh (textile-reinforced mortar), on both sides of the wall. The strengthening solution was found to be efficient for rehabilitating ancient rubble stone masonry walls due to the “three-dimensional” confinement, provided by the steel wires, by offsetting the low cohesive capacity of the mortar used in the walls and thus improving the mechanical resistance and delaying the collapse mechanisms. This study is part of an experimental research program carried out in Universidade Nova de Lisboa, to evaluate structural strengthening solutions for ancient rubble stone masonry buildings. To this end, three specimens of rubble stone masonry walls without strengthening (unreinforced masonry) and other three, with the mentioned strengthening solution, were subjected to compression and shear load tests. Building materials were also tested in order to characterize physical, chemical and mechanical properties.     

Tourists’ walking rhythms: ‘doing’ the Tunis Medina,Tunisia

The contemporary medina of Tunis is intimately connected to the various urban development stages of the city at large. Despite its UNESCO status and undisputable attractions, the medina is peripheral to Tunisian tourism development. Yet its maze of streets is walked on a daily basis by numerous tourists, who bring flair, choreographies and rhythms which also constitute the medina. While there are a growing number of studies focusing on tourists’ movements, using technologies that allow for accurate mapping of timespace trajectories, I argue that we have much to learn from the embodied ways in which tourists move in an unknown terrain. Inspired by Lefebvre’s rhythmanalysis, this paper explores tourists’ rhythms and modes of walking, including their performances, body languages, stops and advances, and gaze interactions. Drawing on a combination of mobile methodologies, interviews and online comments, I argue that tourists engage in many different walking rhythms, which shift quickly according to the situation. It is the complex manner in which tourist bodies, rhythms and urban forms intersect within the contemporary city that contributes to the construction of the city itself.     

Out-of-Plane Seismic Response of Unreinforced Masonry Walls: Conceptual Discussion,Research Needs,and Modeling Issues

ABSTRACT

Modeling unreinforced masonry walls, subjected to seismic loads applied normal to their plane, has received much attention in the past. Yet, there is a general lack of conformance with regard to what aspects of seismic response a computational model should reflect. Boundary conditions are certainly an important aspect, as the response can involve two-way bending or just one-way bending and, in the second case, along vertical or horizontal directions. In this respect, flexural restraint of wall intersections can be significant in addition to size and placement of openings. Moreover, in-plane damage can modify the boundary conditions and the overall out-of-plane performance. Proper modeling of actions is also relevant, as they can be a result of distortions imposed upon wall elements and/or inertial forces along the span of a wall. Axial forces can markedly affect the out-of-plane response of the wall, particularly vertical compressive forces, which can enhance out-of-plane strength. The outcome of static verifications can be more conservative than that of dynamic analyses, but the latter are much more complex to carry out. These topics are discussed with reference to previous research, observations in the field and in the laboratory, as well as numerical analyses on three-dimensional models.     

Simulation of Shake Table Tests on Out-of-Plane Masonry Buildings. Part (IV): Macro and Micro FEM Based Approaches

ABSTRACT

This article presents a study on the out-of-plane response of two masonry structures without box behavior tested in a shaking table. Two numerical approaches were defined for the evaluation, namely macro-modeling and simplified micro-modeling. As a first step of this study, static nonlinear analyses were performed for the macro models in order to assess the out-of-plane response of masonry structures due to incremental loading. For these analyses, mesh size and material model dependency was discussed. Subsequently, dynamic nonlinear analyses with time integration were carried out, aiming at evaluating the collapse mechanism and at comparing it to the experimental response. Finally, nonlinear static and dynamic analyses were also performed for the simplified micro models. It was observed that these numerical techniques correctly simulate the in-plane response. The collapse mechanism of the stone masonry model is in good agreement with the experimental response. However, there are some inconsistencies regarding the out-of-plane behavior of the brick masonry model, which required further validation.     

The Chronology and Taphonomy of the Earliest Aurignacian and Its Implications for the Understanding of Neandertal Extinction

The view that the Châtelperronian is the acculturation of late Neandertals brought about by contact with nearby moderns assumes an age of ca. 40,000 years ago for the earliest Aurignacian. However, the cultural meaning of the dated samples is dubious, either because they were collected from palimpsests containing other archaeological components or because the definition of the associated artifact suites as Aurignacian is not warranted. Wherever sample context is archaeologically secure, the earliest occurrences of the Aurignacian date to no earlier than ca. 36,500 B.P. This is in accordance with the strati-graphic pattern demonstrating the precedence of the Châtelperronian and equivalent technocomplexes of central and eastern Europe, consistently dated by various methods to before ca. 38,000 B.P. Given the Neandertal authorship of the Châtelperronian, it must be concluded that Neandertals had already accomplished their own Middle-to-Upper Paleolithic transition when the first Aurignacian moderns arrived in Europe. Therefore, such a transition occurred simultaneously and independently among European Neandertals and sub-Saharan moderns, across biological boundaries and irrespective of geographical proximity. This suggests that its causes lie in the domain of social process, not in that of putative biological mutations that would have bestowed symbolism upon a lineage of chosen people.     

Landscapes, land use, and the history of territory formation: An example from the Puebloan southwest

Territories are spatial units that encompass the broadest range of a society's land-use behaviors as well as the history of human interactions with the natural landscape. Drawing from published documents pertaining to the North American Indian Land Claims and to the prehistory and history of land use among the Hopi Indians of Arizona, this paper integrates spatial, material, and historical variables of land use behavior (1) to formulate an empirical definition of territory and (2) to develop a generalized life history of territory formation that can be applied explicitly to the archaeological record.     

El misterio de los capı´tulos perdidos de la Cro´nica mexicana de Hernando de Alvarado Tezozomoc

A mediados del siglo diecinueve en una copia manuscrita de la Cro´nica mexicana (CM) de Hernando Alvarado Tezozomoc hecha en 1792, Joaqu?´n Garc?´a Icazbalceta (1825–1894) escribe en la “Advertencia” al lector: Tanto en el Cata´logo impreso del Museo de Boturini, como en el Inventario que hizo de sus papeles el fiscal de la causa y anda unido a esta se dice que esta Cro´nica contiene 112 cap?´tulos. Esta copia solo comprende 110 sin que se advierta ninguna falta en el principio ni en el fin. La cita que hace Dn. Carlos Sigu¨enza del cap?´tulo 82 de esta obra para apoyar un hecho histo´rico (alaman, disertaciones, loc. cit.) corresponde en mi copia al cap 80, por lo que se advierte que la discrepancia de la numeracio´n esta´ en los primeros ochenta cap?´tulos. Esta duda solo pudiera aclararse teniendo a la vista el original que fue de Boturini; pero este lo creo perdido.