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201.
Within the electronics industry, counterfeit electronic components entering the supply chain have steadily become an increasing threat accounting for more than 8 % of global merchandise trade and an annual $600 billion enterprise. Currently, there are not many cost-effective and nonintrusive solutions for counterfeit detection of electronic parts. In this paper, the authors present a statistical approach for detecting counterfeit components based on infrared (IR) analysis by the use of independent component analysis (ICA). As a prominent higher-order statistical analysis technique, ICA is capable of extracting relevant features from IR data. The latest applications and the extended algorithms of ICA have been elucidated for the purposes of classification and identification of counterfeit electronic parts. The theoretical framework of ICA is presented along with extensive experimental results to illustrate its feature extraction function in counterfeit electronic parts detection.  相似文献   
202.
Successful conservation of large terrestrial mammals (wildlife) on private lands requires that landowners be empowered to manage wildlife so that benefits outweigh the costs. Laikipia County, Kenya, is predominantly unfenced, and the land uses in the area allow wide‐ranging wildlife to move freely between different management systems on private land. We used camera traps to sample large mammals associated with 4 different management systems (rhinoceros sanctuaries, no livestock; conservancies, intermediate stocking level; fenced ranches, high stocking level; and group ranches, high stocking level, no fencing, pastoralist clan ownership) to examine whether management and stocking levels affect wildlife. We deployed cameras at 522 locations across 8 properties from January 2008 through October 2010 and used the photographs taken during this period to estimate richness, occupancy, and relative abundance of species. Species richness was highest in conservancies and sanctuaries and lowest on fenced and group ranches. Occupancy estimates were, on average, 2 and 5 times higher in sanctuaries and conservancies as on fenced and group ranches, respectively. Nineteen species on fenced ranches and 25 species on group ranches were considered uncommon (occupancy < 0.1). The relative abundance of most species was highest or second highest in sanctuaries and conservancies. Lack of rights to manage and utilize wildlife and uncertain land tenure dampen many owners’ incentives to tolerate wildlife. We suggest national conservation strategies consider landscape‐level approaches to land‐use planning that aim to increase conserved areas by providing landowners with incentives to tolerate wildlife. Possible incentives include improving access to ecotourism benefits, forging agreements to maintain wildlife habitat and corridors, resolving land‐ownership conflicts, restoring degraded rangelands, expanding opportunities for grazing leases, and allowing direct benefits to landowners through wildlife harvesting. Efectos del Uso Privado de Suelo, Manejo de Ganado y la Tolerancia Humana sobre la Diversidad, Distribución y Abundancia de Mamíferos Mayores Africanos  相似文献   
203.
High relatedness among society members is believed important for the evolution of highly cooperative behaviours, yet queens of many social insects mate with multiple males which reduces nestmate relatedness and imposes also direct costs on queens. While theoretical models have suggested explanations for this puzzling queen behaviour, empirical studies fail to provide consistent answers especially for species with moderate levels of multiple mating. This may result from multiple mating only conferring benefits in some environments, as suggested by recent genetic variance theory and considerations on types of traits, direct costs and benefits. All concur in an expectation of higher levels of multiple mating in more complex or milder environments, and we perform a first, broad test of this idea by comparing mating strategies of queens in Lasius niger ants from northern (harsh, cold stressed) and southern populations (milder, greater bio-complexity). First, we collected new genetic data from Ireland and Southern France and then compared these to data on Swiss and Swedish populations. Queens from northern populations were near exclusively single mated and even at times inbred (in Ireland), whereas southern queens showed high levels of multiple mating, leading to more genetically diverse colonies in the south. Equally, paternity skew was greater in the north, as expected if northern queens only remate when their first mate transfers few sperm. Our findings are consistent with the idea that environment type may affect mating strategies in social insects and calls for an exploration of such effects.  相似文献   
204.
Abstract

The aim of this paper is to use Erikson's approach to human development, and specifically generativity, as a framework by which to explore older people's experiences of environmental stewardship activities. Using data from a large qualitative study of environmental volunteers resident in the coastal fringes of Queensland, Australia, the paper provides important, illustrative, empirical support for Erikson's theory of generativity in later life. Findings suggest that older people are much more likely to connect their environmental actions with the longer-term future, and express a need to leave a lasting legacy for future generations. According to respondents, the later years are a time to contribute to the environment as part of a broader cycle of life. The environment is also an important site for intergenerational activities. Whilst the work presented here is only a small, localized study, use of Erikson's theory of human development as a framework helps demonstrate the importance of a generative response in later life.  相似文献   
205.
Water planning processes in Australia have struggled to account for Indigenous interests and rights in water, including the use of Indigenous knowledge in water management. In exploring the role of Indigenous knowledge in government-led water planning processes, how might tensions between Western scientific and Indigenous knowledges be lessened? Drawing on two case studies from northern Australia we examine how Indigenous knowledge is represented and managed as a different social knowledge to that of Western science in a management context where legal and planning conventions assume priority. The role of Indigenous (social) knowledges in developing options and strategies for sustainable water management is contingent upon the participation of Indigenous people in water planning. We suggest that water planning processes must contain the possibility of an explicit approach to mutual recognition and consequent translation of the conceptual and pragmatic bases of water management and planning in both Western scientific and Indigenous domains.  相似文献   
206.
Journal of Polymers and the Environment - An energy-efficient high throughput pre-treatment of low-density polyethylene (LDPE) using a fast, reactive extrusion (REX) assisted oxidation technique...  相似文献   
207.
Environmental Science and Pollution Research - Heavy metals (HMs) have attracted global attention due to their toxicity, persistence, and accumulation in aquatic fish in the polluted water...  相似文献   
208.
Solemya reidi Bernard 1980 is a gutless protobranch bivalve known to possess intracellular chemoautotrophic bacterial symbionts in its gill. A light and electron microscope study on the embryology and larval development of S. reidi provides data for the bivalve Subclass Cryptodonta. S. reidi spontaneously spawned large eggs (271 m in diameter), which developed within individual gelatious egg capsules. The first several cleavages were equal and a distinct molluscan cross was formed at the animal pole of the embryo, features previously unreported in bivalve development. Lecithotrophic pericalymma larvae (similar to the larvae of paleotaxodont protobranch bivalves and aplacophoran molluscs) hatched at 18 to 24 h and remained in the water column for a further 5 d at 10°C. At hatching, larvae measured from 360 to 440 m in length and from 225 to 265 m in cross-sectional diameter. Definitive adult structures developed within an epithelial locomotory test entirely covered with compound cilia. The test histolysed at metamorphosis and was ingested throught the mouth into the perivisceral cavity. Length and height of the shell following metamorphosis was 433 m (±42 m, n=16) and 282 m (± 29 m, n=13), respectively. Primary data and data from the literature show that the type of larval development in both paleotaxodont and cryptodont bivalves cannot be reliably estimated from egg or prodissoconch sizes.  相似文献   
209.
210.
The impact of ancient fertilization practices on the biogeochemistry of arable soils on the remote Scottish island of Hirta, St Kilda was investigated. The island was relatively unusual in that the inhabitants exploited seabird colonies for food, enabling high population densities to be sustained on a limited, and naturally poor, soil resource. A few other Scottish islands, the Faeroes and some Icelandic Islands, had similar cultural dependence on seabirds. Fertilization with human and animal waste streams (mainly peat ash and bird carcases) on Hirta over millennia has led to over-deepened, nutrient-rich soils (plaggen). This project set out to examine if this high rate of fertilization had adversely impacted the soil, and if so, to determine which waste streams were responsible. Arable soils were considerably elevated in Pb and Zn compared to non-arable soils. Using Pb isotope signatures and analysis of the waste streams, it was determined that this pollution came from peat and turf ash (Pb and Zn) and from bird carcases (Zn). This was also confirmed by 13C and 15N analysis of the profiles which showed that soil organic matter was highly enriched in marine-derived C and N compared to non-arable soils. The pollution of such a remote island may be typical of other ‘bird culture’ islands, and peat ash contamination of marginal arable soils at high latitudes may be widespread in terms of geographical area, but less intense at specific locations due to lower population densities than on Hirta.  相似文献   
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