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171.
Objective: The shape of the current physical and computational surrogates of children used for restraint system assessments is based largely on standard anthropometric dimensions. These scalar dimensions provide valuable information on the overall size of the individual but do not provide good guidance on shape or posture. This study introduced the development of a parametric model that statistically predicts individual child body shapes in seated postures with a few given parameters.

Methods: Surface geometry data from a laser scanner of children ages 3 to 11 (n = 135) were standardized by a 2-level fitting method using intermediate templates. The standardized data were analyzed by principal component analysis (PCA) to efficiently describe the body shape variance. Parameters such as stature, body mass index, erect sitting height, and 2 posture variables related to torso recline and lumbar spine flexion were associated with the PCA model using regression.

Results: When the original scan data were compared with the predictions of the model using the given subject dimensions, the average root mean square error for the torso was 9.5 mm, and the 95th percentile error was 17.35 mm.

Conclusions: For the first time, a statistical model of child body shapes in seated postures is available. This parametric model allows the generation of an infinite number of virtual children spanning a wide range of body sizes and postures. The results have broad applicability in product design and safety analysis. Future work is needed to improve the representation of hands and feet and to extend the age range of the model. The model presented in this article is publicly available online through HumanShape.org.  相似文献   

172.
Summary Lifetime reproductive success (LRS) of male (N=103) and female (N= 66) spotted sandpipers (Actitis macularia) was studied for 13 years of a 17-year study at Little Pelican Island, Leech Lake, Minnesota. There was no sex difference in longevity, but females had significantly more mates, eggs, chicks, fledged young, and young returning in subsequent years than did males. Variance in LRS was partitioned into five life-history components: longevity (L), mates per year (M), eggs per mate (E), proportion eggs hatched (H), and proportion of chicks fledged (F). For both sexes, F accounted for the greatest proportion of variance in LRS (males, 43%; females, 47%), followed by L (males, 26%; females, 43%) and H (males, 21%; females, 28%). Positive covariance between H and F was consistent with predator-caused clutch and brood loss. Contrary to our expectations, males had a higher coefficient of variation in reproductive success than did females. This was because males were relatively more likely than females to produce no young.Offprint requests to: L.W. Oring at the current address  相似文献   
173.
Riparian forest restoration has become a major focus of watershed initiatives to improve degraded stream ecosystems. In urban watersheds, however, the ability of riparian forests to improve stream ecosystems may be diminished due to widespread, upland disturbance. This paper presents the methodology and some preliminary results from the first year of fieldwork on a 3-year project designed to assess the ecological benefits of riparian reforestation in urban watersheds. The study is based on an integrated, multidisciplinary sampling of physical, chemical, and biological attributes at forested and non-forested sections of 12 streams with different amounts of urban developement within their watersheds. Restored sections of three streams are also being monitored over the 3-year duration of the project. Sampling and analysis will continue through December 2000.  相似文献   
174.
175.
Kabul and Monrovia, the respective capitals of Afghanistan and Liberia, have recently emerged from long-lasting armed conflicts. In both cities, a large number of organisations took part in emergency water supply provision and later in the rehabilitation of water systems. Based on field research, this paper establishes a parallel between the operations carried out in the two settings, highlighting similarities and analysing the two most common strategies. The first strategy involves international financial institutions, which fund large-scale projects focusing on infrastructural rehabilitation and on the institutional development of the water utility, sometimes envisaging private-sector participation. The second strategy involves humanitarian agencies, which run community-based projects, in most cases independently of the water utilities, and targeting low-income areas. Neither of these approaches manages to combine sustainability and universal service. The paper assesses their respective strengths and weaknesses and suggests ways of improving the quality of assistance provided.  相似文献   
176.
As the concept of sustainability broadens to include social aspects, sustainability organisations must embrace strategies that allow them to more effectively address community issues and procedural concerns. Biosphere reserves (BRs) and model forests (MFs) advocate strongly for community engagement to achieve place-based sustainability; in practice, however, these organisations have had variable success in effectively engaging community residents and addressing their needs and interests. In this paper, we offer a framework for place-based governance for sustainability that is used to compare strategies used in BRs and MFs operating in the Maritime Provinces of Canada with the operations of Vibrant Communities, an anti-poverty organisation that operates locally in Saint John, New Brunswick. We draw attention to three imperatives: comprehensive understanding, community empowerment, and community-based outcomes, and five procedural drivers: local leadership, strong networks, diverse community engagement, learning together, and information sharing. Based on our results, we provide greater clarity on processes that address the imperatives and mobilise the drivers of effective place-based governance for sustainability. Our results suggest that there is a need for theory and practice to advance beyond current understandings of sustainability governance to enhance the capacity of organisations seeking to implement community-based sustainability strategies.  相似文献   
177.
Renewed political and commercial interest in the resources of the Arctic, the reduction in the extent and thickness of sea ice, and the recent failings that led to the Deepwater Horizon oil spill, have prompted industry and its regulatory agencies, governments, local communities and NGOs to look at all aspects of Arctic oil spill countermeasures with fresh eyes. This paper provides an overview of present oil spill response capabilities and technologies for ice-covered waters, as well as under potential future conditions driven by a changing climate. Though not an exhaustive review, we provide the key research results for oil spill response from knowledge accumulated over many decades, including significant review papers that have been prepared as well as results from recent laboratory tests, field programmes and modelling work. The three main areas covered by the review are as follows: oil weathering and modelling; oil detection and monitoring; and oil spill response techniques.  相似文献   
178.
Consensus-based multi-stakeholder forms of environmental governance involving government, private and civil society actors, have become popular for advancing sustainability, but have been criticized for failing to achieve procedural justice objectives including recognition, participation and strengthening capabilities. Yet, how such models have functioned within non-governmental organizations dedicated to advancing sustainability has been underexplored. This paper assesses the procedural elements of consensus-based multi-stakeholder models used within Canadian biosphere reserves and model forests, two organizations working to address environment and sustainability issues. We draw on strategic documents and semi-structured interviews from five organizations in Canada to analyze their governance structures and processes against a framework for procedural justice. We find the organizational structure reproduces elitism and professionalism associated with stakeholder models more generally and reproduces challenges associated with recognition, participation and building capabilities found in other stakeholder approaches. Meeting broader sustainability challenges requires organizations to address procedural justice issues in addition to their traditional environmental concerns.  相似文献   
179.
Researchers of adaptive capacity and sustainable livelihoods have frequently used social, cultural, human, economic and institutional capitals to better understand how rural and resource-dependent communities address environmental, social and economic stresses. Yet few studies have considered how men and women contribute differently to these capitals to support community resilience overall. Our research sought to understand the differential contributions of Sami men and women to the adaptive capacity of reindeer husbandry and reindeer herding communities in northern Sweden. Our focus revealed a gendered division of labour in reindeer herding as an economic enterprise as well as gendered contributions to a broader conceptualization of reindeer husbandry as a family and community-based practice, and as a livelihood and cultural tradition. Based on our results, we recommend that community resilience be enhanced by generating more opportunities for men to achieve higher levels of human and economic capital (particularly outside of herding activities) and encouraging women to contribute more directly to institutional capital by participating in the formation and implementation of legislation, policies and plans.  相似文献   
180.
In order to study the effects of fabric filter parameters when filtering an actual industrial effluent stream, it is necessary to vary these parameters in the field. A mobile fabric filter system has been designed, fabricated and operated to provide this information. The design characteristics and some preliminary field data collected with this system are summarized.  相似文献   
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