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1.
Whilst the advantages of the application of Land Readjustment (LR) are well known, there are nevertheless numerous countries in which application of LR is difficult or has not been successful. In its analysis of land readjustment constraints, conditions and the international practice, this paper contributes to improving the implementation of an LR system, particularly with respect to the management process. At the international level, management models in seven countries were studied: Australia, France, Germany, Japan, South Korea, Spain and Sweden. In Portugal, three case studies in the municipalities of Almada, Coimbra and Lisbon were selected, with semi-structured interviews being conducted with the respective managing entities. The management models are distinguished by the type of initiative and leadership processes, relations among stakeholders, managing entities and operating rules. It can be concluded that the role of the public authority as the process facilitator from the very initial stages, the existence of a managing entity and a board of specialists, and the legal conditions governing expropriation are key factors for the improvement of land readjustment management.  相似文献   
2.
In the fourth millennium BP, there were major environmental and cultural changes on the Andean altiplano of South America, but the chronology remains vague. A recent synthesis describes a slow, gradual transition from hunting and gathering to agropastoralism. This proposal is tested by refining the date of the onset of more humid and stable conditions, around 3550 cal BP, based on a Bayesian model of 26 dates from Lake Wiñaymarka and an updated calculation of the lacustrine offset. This is compared to Bayesian models of 191 dates from 20 archaeological sites, which incorporate a number of recently processed radiocarbon dates. A synthesis is presented of 15 full coverage surveys, a summed probability distribution, and a Bayesian model of the transition to ceramics, which together support a scenario of a very rapid demographic increase. Fourteen models from archaeological sites are cross-referenced in a composite model, which identifies a brief, altiplano-wide emergence of agropastoralism with starting and ending boundaries of 3540 and 3120 cal BP, respectively. This starting boundary correlates strongly with the onset of improving environmental conditions, indicating synchronous cultural and environmental change. The suite of accelerating cultural changes included a marked reduction in mobility, a demographic surge, increased subsistence diversity, the adoption of ceramics, farming and the integration of camelid herding into a remarkably resilient economic strategy still in use today. This is a highly relevant but yet to be used comparative case study for the variable tempos of ‘big histories’, and ecocultural interactions that generate rapid, emergent episodes of wide-spread and enduring cultural change.  相似文献   
3.
This paper aims to trigger discourse about the emergence of a new type of social scientific model — Exploratory Models — which draw on Big Data, computer modeling and interdisciplinary research to tackle complex social scientific processes. First, we define Exploratory Models referring to Batty and Morgan and Morrison. We then present changes to the traditional modeling paradigm. We show how Exploratory Models circumvent challenges related to the idiosyncracy, self-reflexivity and acceleration of social phenomena, which limit predictive effectiveness of traditional models. We show that Exploratory Models are better equipped to tackle complex problems due to their capacity to process heterogeneous datasets. Having established that Exploratory Models are predominantly problem- and data-driven, we emphasize that scientific theory is indispensable to their progress. Finally, the development of an integrative platform is suggested as a way of maximizing the benefits of this approach. Discussion concludes by flagging areas for further research.  相似文献   
4.
Ancient iron tie-rods are handcrafted elements with large geometric irregularities, due to production techniques (they are shaped by hammering and linked by hot-forging) and corrosion processes. In common practice, their cross section (that is one of the main parameter to assess their strength) is manually measured on site with a manual caliber. By analyzing a set of detailed three-dimensional (3D) digital surveys of real ancient tie-rods, this study provide an evaluation of the errors made by in-situ manual geometric measurements. In particular, it shows that, in some cases, manual on-site survey is sufficiently reliable and has errors that fall below 10%. Moreover, it shows that when tie-rods have high corrosion levels in hidden zones (typically those close or within the retaining walls) the on-site survey of visible parts only may produce far greater errors that exceed 100%, leading to a strong overestimation of the cross-section of the tie. The ongoing study is a first step toward the definition of correction coefficients to be applied to the on-site manual measurements of ancient tie-rods, with the final aim to improve the reliability of structural analyses.  相似文献   
5.
This paper evaluates chronological trends in the presence and absence of domestic animal bone (sheep, goat, and cattle) and pottery in Namaqualand, the proposed gateway to the rest of South Africa for early herders or hunter-gatherers with sheep and ceramics. We update date calibrations with local ΔR corrections and mixtures of recent calibration curves and include five previously unpublished dates. We use histograms of calibrated medians, sorted in 100-year bins, to assess sustained regional patterns with dates associated with domestic animal bone and pottery (n = 73). While too small to be useful as a population proxy, the current set of dates does reveal three pulses of occupation separated by two clear gaps, which we evaluate with a Bayesian model of three sequential phases. The model's boundaries are used as estimates of the dates of Early (AD 80–210), Middle (AD 490–790), and Late (AD 1180–1690) occupational phases separated by two substantial lapses of 280 and 380 years, respectively. The alternating phases of presence and absence are suggestively correlated with climate shifts, leading to a discussion of the idea that effective moisture was a crucial factor in choosing whether to occupy Namaqualand. The set of archaeological dates has greater temporal and spatial resolution than many regional climate data, so we suggest that these trends may more accurately reflect the variable conditions specific to Namaqualand, at least until they are refined by future climate research.  相似文献   
6.
Tie-rods are essential structural elements, which have been employed for centuries in masonry historical buildings, either during the construction or in successive strengthening interventions, with the aim of containing dangerous horizontal actions. The actual work conditions of these tie-rods, which are strongly influenced by their load history, are difficult to be quantified theoretically, and an effective method for their measure is of great importance in order to ensure the efficiency of these elements during the time and the stability of the entire building. Common measurements are often carried out adopting models based upon significant simplifications, like, for example, hinges at the extremities. These assumptions, rarely represent the real work conditions for anchorages. In this work, a non-destructive testing method is presented, based upon sophisticated dynamical models that can take into consideration many of the circumstances neglected by the simplified models. Four case studies are extensively described, trying to embrace the most common situations in term of peculiar features of the building, structural configuration, and load history. The discussion of the results yields the safety margin of the rod with respect to the material failure and provides important indications about the overall stability of the whole building.  相似文献   
7.
Ancient human migrations provide the critical genetic background to historical and contemporary human demographic patterns. However, our ability to infer past human migration events, especially those that occurred over rapid timescales, is often limited. A key example is the peopling of Polynesia, where the timing is relatively well defined, but the exact routes taken during the final stages and the source populations are not. Here, we discuss the technical limitations of current methods for inferring rapid human migration events, using the final stages of Polynesian migration as an example. We also introduce a promising new proxy method to infer human migrations—patterns of bacterial evolution within ancient dental calculus (calcified plaque). While we focus on Polynesia, this method should be applicable to other past migrations, enhancing our understanding of human prehistory and revealing the crucial events that shaped it.  相似文献   
8.
This study examines the interrelationship between external political support, internal organizational factors, and red tape, using a sample of information managers from state health and human service agencies. The study defines a red tape model and tests the model by structural equation modeling method. The study finds that political support has a direct effect on red tape. The higher the political support, the lower the level of red tape. The study also confirms an indirect effect of political support on red tape, mediated by developmental culture. Indirect effect through goal clarity has the correct sign but is not statistically significant. Practical recommendations are made for the political environment to provide the opportunity for managerial reforms that are often advocated.  相似文献   
9.
ABSTRACT

The interest in automatic modal parameter extraction techniques has increased significantly in recent years because of the rising demand for Continuous Structural Health Monitoring (CSHM) of civil structures and infrastructures. The wider use of CSHM is related to its capability for early damage detection and therefore to its usefulness for planning maintenance and strengthening interventions. This article presents the main steps followed in creating a robust routine to run on an online basis the first-ever Continuous Vibration-Based Structural Health Monitoring (CVB-SHM) of a large masonry oval dome, i.e., the dome of the Regina Montis Regalis Basilica, also known as Sanctuary of Vicoforte. The procedure uses an output-only stochastic subspace identification method complemented by an automatic analysis applied to identification results, which are typically provided in terms of stabilization diagrams. In this study, the fully automatic procedure also includes a hierarchical clustering algorithm to separate authentic from spurious modes.  相似文献   
10.
In the literature on territorial innovation systems there is a constant tension between the effect of endogenous and exogenous factors and their relative importance. In order to address this tension several approaches have sought to conceptualize the relational and multi-scalar dimension of innovation and to explain how external knowledge and economic flows in conjunction with regional contexts combine to produce regional growth, stagnation or decline. This paper will contribute to this debate, while also highlighting that even at the local level there is substantial heterogeneity between firms. It will also shed light on the role of intermediary organizations that can help address information and power asymmetries between multinational corporations and less competitive local firms. Empirically it will draw on the case study of the Portuguese moulds industry, which has successfully adapted to shifts in the global economy by drawing on local resources while also remaining integrated into global value chains.  相似文献   
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