Liquefaction-Induced Lateral Load on Pile in a Medium Dr Sand Layer

One-g shake-table experiments are conducted to explore the response of single piles due to liquefaction-induced lateral soil flow. The piles are embedded in saturated Medium Relative Density (Dr) sand strata 1.7–5.0 m in thickness. Peak lateral pile displacements and bending moments are recorded and analyzed by uniform and triangular pressure distributions. On this basis, the observed levels of pile bending moment upon liquefaction suggest a hydrostatic lateral pressure approximately equal to that due to the total overburden stress. Using the experimental data, comparisons with current recommendations are made, and the Showa Bridge case history is briefly assessed.     

Assessment of the Lines of Torres Vedras defensive system with visibility analysis

A method to assess the coherence of defensive systems based on the individual and combined visual coverage of fortifications is presented. The case study is the complex fortification system of Lines of Torres Vedras, around Lisbon, Portugal, activated in the first decade of the 19th century to halt the French armies of Napoleon in the Peninsular War. As messages between fortifications are known to have been exchanged visually by semaphore, GIS-based viewshed calculations enabled the assessment of the system's coherence and the exploration of how the undocumented communication with the defensive forces' headquarters in Lisbon might have been achieved. Results show that the defensive system with its two lines was highly effective per se with respect to the visual coverage of the terrain and the exchange of messages between fortifications, but it could have been improved with minor changes to the location of communication devices. It is also found that communication with the headquarters in Lisbon was not adequate, suggesting that additional devices were needed.     

First dendroarchaeological dates of prehistoric contexts in South America: chullpas in the Central Andes

Despite the existence of long-lived tree species with excellent tree-ring characteristics, the use of dendrochronological techniques for dating archaeological contexts has been very limited in South America. Recent research in the Bolivian Altiplano of the Central Andes has yielded a network of Polylepis tarapacana chronologies that goes back to the 13th century. This species was regularly used by local populations since pre-Columbian times as raw material for beams, lintels, hooks and other architectural features in houses, storage chambers, and sepulchers. The aim of this study is to argue in favor of the potential of P. tarapacana for providing high resolution dates of significant archaeological events during the pre-Columbian era. The chronology of chullpas (burial towers and storage chambers) in the southern Andean Altiplano is used as a case study. Growth rings from P. tarapacana have provided several centennial-length dendrochronological records including a reference regional chronology covering the last 786 years in the Central Andean highlands. Based on this long reference chronology calendar years were assigned to woody pieces from pre-Hispanic chullpas. Dendroarchaeological results are consistent with contextual evidence and most radiocarbon dates from woody samples and related archaeological items. Our results indicate that P. tarapacana has a high potential for providing annually-resolved tree-ring dates for archaeological contexts in the Altiplano since the early 13th century.     

Surviving in the margins of a genocide case in the making: recognizing the economy of testimony at stake in research on political violence

ABSTRACT

In this article, we aim to draw attention to the hopes, frustrations and disillusions that so-called ‘transitional justice’ projects produce in drastically poor, war-torn, historically marginalized but politicized Indigenous communities. Drawing on extensive ethnographic research we conducted separately between 1982 and 2010 in Guatemala and Mexico, we describe the ways in which the world came to know about Finca San Francisco’s massacre, committed by the Guatemalan army on 17 July 1982, as part of its scorched earth policy. We then look at the various forms of reparations its survivors have been the subject of. In so doing, we focus more specifically on how the Center for Human Rights Legal Action (CALDH), the non-governmental human rights organization that was behind the Ríos Montt genocide case, mobilized Finca San Francisco’s massacre survivors to become participants in the trial. After examining how the survivors of Finca San Francisco responded to CALDH’s mobilization efforts, we reflect on the kind of ‘gift’ these survivors expected in return for their stories of annihilation and destruction. Our goal is to bring to light the ‘economy of testimony’ that human rights activists, journalists or social scientists become entangled in once they ask genocide survivors to testify about the brutal deaths of their loved ones.     

Multiple Allocation Hub Location Model with Fixed Arc Costs

This article formulates a model to analyze the role of fixed costs in the design of optimal transportation hub networks. The primary purpose of this article is to better model costs in hub networks, an issue that has attracted considerable attention. This article allows particular versions of hub networks to emerge from the cost structure, rather than by imposing a rigid predefined connectivity protocol. The article integrates modeling approaches from an environmental hub location model with the three‐index formulation of Ernst and Krishnamoorthy to produce a hub location model with fixed and variable costs for all arcs. Our goal is to demonstrate how the inclusion of a richer cost model in transportation hub location can generate a wide range of different network types, depending on the relative magnitudes of the cost elements. While the existence of special case network solutions is well known and has been exploited in optimization, the current research provides added insight to the cost of flow in a more, or less, connected hub network. Eight fundamental prototype networks are derived as special cases, and some additional unanticipated network types also emerge. The results are illustrated with a standard CAB25 data set.     

Critical Assessment of Intensity Measures for Seismic Response of Italian RC Bridge Portfolios

The seismic assessment of a road network depends largely on the characterization of the fragility of its bridge components. The accuracy of bridge seismic demand estimates and the use of proper intensity measures (IM) will significantly influence such task. The available literature has mainly focused on buildings or a limited number of bridge configurations and IMs, which may not be representative for bridge portfolio assessment studies. In this paper, the correlation quality between a larger pool of traditional and innovative IMs and the nonlinear dynamic response of typical Italian RC bridges is investigated to identify the best-performing IMs.     

Evolution of the Labor Market in a Regional City:The Changing Economic Performance of Emigrants from Mexico City*

Abstract. This paper draws on micro‐level data to fully inform the debate on decentralization and regional development. Using labor‐income trajectories of emigrants from Mexico City, the paper analyzes how the labor market in a regional city, Leon, evolves. Results from the econometric model suggest that migrants’ labor‐income trajectories differ between the large agglomeration and the regional city in an early stage of the evolution of the labor market, but converge in a later stage. Specifically, the slope of the earning function for recent migrants is steeper and statistically different from the slope for early migrants. The findings presented in this paper enrich the existing theory by providing microfoundations to a typically macroeconomic area of research and enable policy makers to better understand the processes underpinning the evolution of regional labor markets.     

Evaluating the Risk of Plant Closure in the Automotive Industry in Spain

This study looks at the reorganization of production in the context of a multi-plant firm in the automotive industry. Changes in such firms may result in the closure of some plants and/or the opening of others. The article provides a method for assessing the risk of plant closure, and then applies that method to a specific case: the automotive plants located in the Spanish region of Navarre. This entails acknowledging the factors that increase what has come to be known as the “degree of vulnerability” of the plant, including sunk costs and relative productivity levels. This paper can also be understood as a source of information for designing developmental after-care programmes for foreign direct investors in the periphery of the European Union.     

Archaeological research on HMS Swift: a British Sloop-of-War lost off Patagonia, Southern Argentina, in 1770

HMS Swift was a British sloop-of-war which sank off the coast of Patagonia, Southern Argentina, in 1770. Since 1997 the Underwater Archaeology Programme of the National Institute of Anthropology has taken charge of the archaeological research conducted at the wreck-site. This article presents an overview of the continuing Swift project and the different research lines comprised in it. The latter cover aspects related to ship-construction, material culture and natural site-formation processes.
© 2006 The Authors