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991.
Haider Al Abadi Vidal Paton-Cole Emad Gad Nelson Lam Vipul Patel 《Journal of Earthquake Engineering》2019,23(5):793-809
Free-standing rigid objects and structures are dominantly found to exhibit rocking behavior and can be vulnerable to overturning during an earthquake as demonstrated by numerous past earthquake events. Such objects are typically considered to be displacement sensitive with their rocking response being well presented by the Peak Displacement Demand (PDD) parameter of the supporting floor’s motion. This in turn can be directly related to an object’s width (along the direction of motion) for assessing its vulnerability to overturn. Such findings have been sufficiently justified by refined dynamic analysis supported by experimental evaluations which were based on rigid blocks with uniform geometric format (i.e., regular in their mass distribution). However, vulnerable rocking objects can be asymmetric and accordingly their sensitivity to floor displacement cannot be directly related to their width. The key parameter which defines irregular objects’ response to rocking motion is represented by the degree of eccentricity of their center of mass. In this study, the well-known rocking equation of motion is reconfigured and devised to model the rocking responses for 280 irregular objects undergoing eight earthquake motions which included artificial and recorded earthquakes. Analytical results obtained from solving the adjusted equation of motion were evaluated with sophisticated finite element (FE) models simulating the 280 irregular cases. This experimentally validated FE modeling approach was found to be time- and cost-effective for understating the rocking behavior of asymmetric objects as well as clarifying an interesting relationship between the object’s damping level and the condition of the supporting base (i.e., whether being provided with supports at the points of rotation or not). The rocking response of irregular objects was found to be highly influenced by the level of eccentricity of the object when excited by motions with high displacement amplitudes, while such influence was not found noticeable by wider objects. Based on the developed trends between the maximum top displacement of irregular objects and the PDD, an expression for estimating the rocking amplitudes is proposed which is a function of the object’s eccentricity. 相似文献
992.
Jay Rajapakse Semone Rainer‐Smith Graeme J. Millar Peter Grace Allison Hutton Wendy Hoy Christine Jeffries‐Stokes Brian Hudson 《Geographical Research》2019,57(2):178-188
Chronic kidney disease (CKD) is important in the fields of public health and health geography because of its heavy burden on the health system and high cost of treatment in its advanced stages. The causes of CKD are associated with diabetes and hypertension, but in some parts of the world, the disease occurs in the absence of these factors. Researchers identify this condition as CKD of “unknown” causes (CKDu). CKDu is a multi‐factored health problem and one suspected causal factor is contaminated drinking water. The disease occurs globally but is found in particularly high concentrations among people of certain ethnic and disadvantaged social groups living in very different locations around the world. CKD has become endemic in Western Australia where hospital admissions for Aboriginal people requiring renal dialysis or treatment for diabetes are much higher than for the general population. The possible proportions of CKDu cases among the CKD patients are unknown. This study examines the drinking water quality among communities such as these. Water chemistry analysis in these areas indicates that the nitrate and uranium content greatly exceed officially recommended levels. Most of these communities rely on raw groundwater to supply their domestic needs, and it is very likely that the people are unwittingly ingesting high levels of nitrates and uranium, probably including uranyl nitrates. Very few such remote communities have access to treated drinking water, and cost‐effective water treatment systems are required to provide potable water at the local scale. 相似文献
993.
Falling trees commonly turbate soils in primary forest, creating characteristic edaphic patterns related to pit and mound topography. Vernal ponds with associated mounds were observed in mineral soils on a treeless plain in subalpine Tasmania, Australia. The hypothesis that paired ponds and mounds on the plain originated as pit and mound features in forests that were later destroyed by fire was tested by comparing the soils and landforms caused by recent tree falls in adjacent forest with those on the plain. The soil characteristics, orientations, and dimensions of the ponds and mounds were consistent with a tree fall origin, although rare secondary ponds on the tops of mounds may derive from the burrowing activities of the medium‐sized marsupial, Vombatus ursinus (common wombat). The characteristics of pond and mound soils suggested that most were hundreds to thousands of years old, with the ponds persisting because of differences in deflation, deposition, and organic matter formation between themselves and adjacent persistently dry land. 相似文献
994.
Cristina García‐Hernndez Jesús Ruiz‐Fernndez Benjamín Gonzlez‐Díaz 《Geographical Research》2019,57(2):189-203
The snowstorms that affected the Cantabrian Mountains in the winter of 1888 caused unprecedented damage, and the absence of a “resilient approach” to this episode had several consequences worth further consideration. In this study, we explored interconnections between and among memory, social learning, and resilience by surveying the affected landscapes, conducting interviews with current residents, and reviewing historical sources such as press archives. The mixed method has enabled us to examine the construction and transmission of respondents' memories and to link those narratives to our reading of the presence or absence of risk mitigation actions—especially against snow avalanches. Our analysis has established that the 1888 snowstorms are remembered down the decades in ways that downplay risk, neglect social learning and changes to community practices and capacities to cope with uncertainties, and fail to shape preventive measures against future disasters. These insights have relevance for those interested in how archival research, field observations, and contemporaneous interviews can aid understandings of inherited memory, social learning, and resilience. 相似文献
995.
996.
This article examines the dynamic nature with which independent accountability mechanisms operate. Focusing on the World Bank, the authors argue that its Inspection Panel evolves according to internal and external pressures. In seeking to achieve equilibrium, and protect its authority and independence, the Panel has gone through several distinct phases: negotiation, emergence, protracted resistance, assertion of independence and authority, renewed tension, and contestation. The core novelty of the article is its application of concepts from outside the field of development studies — notably institutional accountability from the governance literature, and judicialization from the legal studies literature — to the topic of the Inspection Panel. Examining the Panel in this way demonstrates that accountability mechanisms represent a hybrid of transnational governance influenced by a range of actors including project‐affected peoples, national governments, managers and development donors. Accountability in development finance is about competing interests as well as competing conceptions and expectations of accountability. In such a complex and multi‐scalar system, the Panel is not only concerned with delivering well‐researched investigation reports; it is also an entity seeking to ensure its own survival, as well as an arbiter of its own brand of legitimacy and accountability. 相似文献
997.
We propose a new estimator of spatial autocorrelation of areal incidence or prevalence rates in small areas, such as crime and health indicators, for correcting spatially heterogeneous sampling errors in denominator data. The approach is dubbed the heteroscedasticity‐consistent empirical Bayes (HC‐EB) method. As American Community Survey (ACS) data have been released to the public for small census geographies, small‐area estimates now form the demographic landscape of neighborhoods. Meanwhile, there is growing awareness of the diminished statistical validity of global and local Moran’s I when such small‐area estimates are used in denominator data. Using teen birth rates by census tracts in Mecklenburg County, North Carolina, we present comparisons of conventional and new HC‐EB estimates of Global and Local Moran’s I statistics created on ACS data, along with estimates on ground truth values from the 2010 decennial census. Results show that the new adjustment method dramatically enhances the statistical validity of global and local spatial autocorrelation statistics. 相似文献
998.
This study aims at developing a data‐driven and bottom‐up spatial statistic method for identifying regions of anomalous spatial interactions (clusters of extremely high‐ or low‐value spatial flows), based on which it creates a spatial flow weights matrix. The method, dubbed flowAMOEBA, upgrades a multidirectional optimum ecotope‐based algorithm (AMOEBA) from areal data to spatial flow data through a proper spatial flow neighborhood definition. The method has the potential to dramatically change the way we study spatial interactions. First, it breaks the convention that spatial interaction data are always collected and modeled between spatial entities of the same granularity, as it delineates the OD region of anomalous spatial interactions, regardless of the size, shape, scale, or administrative level. Second, the method creates an empirical spatial flow weights matrix that can handle network autocorrelation embedded in spatial interaction modeling, thus improving related policy‐making or problem‐solving strategies. flowAMOEBA is tested and demonstrated on a synthetic data set as well as a county‐to‐county migration data set. 相似文献
999.
1000.
Olivia Barnett‐Naghshineh 《Oceania; a journal devoted to the study of the native peoples of Australia, New Guinea, and the Islands of the Pacific》2019,89(2):220-236
For those women living in villages within accessible range of Goroka town, it is the norm to sell fresh produce in the Goroka market. Fresh produce trading, or maket in Tok Pisin, is common for women throughout the country. To see men selling food in the Goroka market is significantly less common, and those who do, usually sell foods brought from outside of Goroka. The gender divisions that exist in and around the marketplace today in Goroka are maintained through discourses of emotions and practice, specifically the notion of sem (Tok Pisin: shame, embarrassment). As part of a 12‐month ethnographic research project on gender relations in and around the Goroka market, I spoke with market vendors, amongst others living in and around Goroka, about why men do not market. I also interviewed some of the few men who do sell fresh produce in the market. Based on these men's explanations and those of others with whom I spoke, I suggest that these sellers exhibit aspects of masculinity that are caring for their families, putting shame second, and justifying this by their aspirations to transform their and their loved ones’ lives through education and business. These men demonstrate an emergent form of masculinity that both includes and contests aspects of hegemonic masculinity in the Highlands. Whilst selling fresh produce in the marketplace is deemed embarrassing and shameful for the majority of men, those who sell regardless justify doing so by pointing to the importance of providing for their families and loved ones. 相似文献