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Robert U. Ayres Stedman B. Noble 《Journal of the Air & Waste Management Association (1995)》2013,63(3):216-224
The study considers a range of possible effects on the transportation industry, satellite industries, the labor market, and the economy which may be anticipated in the event mass production of unconventional low emission automotive propulsion systems should occur, whether as a consequence of federal intervention, or not. A postulated 1 976 Otto Cycle Internal Combustion Engine equipped with a dual catalyst manifold reactor and other “conventional” emission control devices was compared in detail with a Regenerative Free Turbine Engine and a Rankine Cycle Engine, as specified by the contracting agency. Manufacturing costs, operating and ownership costs, consumer demand, inter-industry effects, employment, resource requirements, and international trade implications were analyzed in depth under a number of plausible sets of policy constraints and parametric variations. Principal conclusions are that conversion over a 10 year period is feasible, that manufacturing cost differentials are less critical than fuel consumption and cost differentials, that industry/employment impacts are minor, and that resource/trade effects are dominated by petroleum imports. Implications for federal policy are discussed. 相似文献
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Lianou M Chalbot MC Kavouras IG Kotronarou A Karakatsani A Analytis A Katsouyanni K Puustinen A Hameri K Vallius M Pekkanen J Meddings C Harrison RM Ayres JG ten Brick H Kos G Meliefste K de Hartog J Hoek G 《Environmental science and pollution research international》2011,18(7):1202-1212
Purpose
The concentrations of PM10 mass, PM2.5 mass and particle number were continuously measured for 18 months in urban background locations across Europe to determine the spatial and temporal variability of particulate matter.Methods
Daily PM10 and PM2.5 samples were continuously collected from October 2002 to April 2004 in background areas in Helsinki, Athens, Amsterdam and Birmingham. Particle mass was determined using analytical microbalances with precision of 1 ??g. Pre- and post-reflectance measurements were taken using smoke-stain reflectometers. One-minute measurements of particle number were obtained using condensation particle counters.Results
The 18-month mean PM10 and PM2.5 mass concentrations ranged from 15.4 ??g/m3 in Helsinki to 56.7 ??g/m3 in Athens and from 9.0 ??g/m3 in Helsinki to 25.0 ??g/m3 in Athens, respectively. Particle number concentrations ranged from 10,091 part/cm3 in Helsinki to 24,180 part/cm3 in Athens with highest levels being measured in winter. Fine particles accounted for more than 60% of PM10 with the exception of Athens where PM2.5 comprised 43% of PM10. Higher PM mass and number concentrations were measured in winter as compared to summer in all urban areas at a significance level p?0.05.Conclusions
Significant quantitative and qualitative differences for particle mass across the four urban areas in Europe were observed. These were due to strong local and regional characteristics of particulate pollution sources which contribute to the heterogeneity of health responses. In addition, these findings also bear on the ability of different countries to comply with existing directives and the effectiveness of mitigation policies. 相似文献3.
“Black Spot” a necrotic shell disease in crustacea, is a naturally occurring condition in crabs (Cancer pagurus) and is more common in older animals, where the moult frequency is reduced. The results of field observations in various commercial crab fisheries suggest that the incidence of “Black Spot” shell disease is higher in lightly fished populations (e.g. S. W. Ireland) than in established fisheries, where intensive exploitation results in the removal of larger (older) crabs from the stock. These observations are used to explain suggestions by other workers that the incidence of shell necrosis is high in areas used for dumping sewage sludge where fishing intensity is low. 相似文献
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An information-based model of the “optimal control” type is developed using concepts from information theory to explore the dynamics of fossil resource exhaustion and the phenomenon of substitution by other forms of capital and technological knowledge. All exhaustible resources stocks and forms of capital (and knowledge) are taken to be equivalent to forms of information in the physical sense. It is shown that, with optimal policies, the planning period, or cycle, has several distinct phases, with different optimal investment patterns. The model has two important qualitative implications: (1) economic growth rates are inherently discontinuous and (2) the model predicts an evolutionary structural change, viz., the creation of a new sector in response to the progressive exhaustion (or obsolescence) of previously essential resources or capital stocks. A multiperiod extension is suggested, leading to a tentative explanation for the Kondratieff long-wave phenomenon. 相似文献
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Michiel Wichers Wilson Siguemasa Iramina Sérgio Médici de Eston Anna Luiza Marques Ayres da Silva 《Environmental monitoring and assessment》2018,190(1):40
Mining plays an important role in Brazilian exports. On the other hand, large urban centers like São Paulo, with approximately 21 million inhabitants, also demand an increasing domestic consumption of natural resources, such as construction aggregate. There are many quarries located in the surroundings of urban centers in Brazil, competing with the growth of urbanized areas. Such proximity leads to a series of conflicts involving quarries and surrounding communities, where the increase in noise levels is highlighted. Operations in quarries, in general, are intermittent. Noisier equipment, such as drilling rigs and primary crushers, operates only a few hours during the day, while other operations, such as screening and secondary and tertiary crushing, are more constant. This paper presents a study carried out in a quarry located near São Paulo, where in addition to conventional short term noise measurements at surrounding receptors, one noise monitoring station was installed, allowing to identify the noisiest moments during the quarry operating time. Through data transmitted by wireless technology, it was possible to follow the noise variations emitted from mining activities in real time and observe the noisiest events that were recorded for events that exceeded the established standards. A mobile application associated to this monitoring station facilitated the quarry’s manager and employees to access immediately the monitoring information. Therefore, by using this system, it was possible to evaluate the effectiveness of noise reduction measures already taken and indicate what steps still need to be held. 相似文献
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This is a report of a social environmental audit of urban renewal schemes based on an investigation of environmental hazard risk perceptions of people in their homes, workplaces and other places of urban activity, in the vicinity of five major renewal sites in Sandwell, West Midlands, UK. The selection of the renewal schemes was designed to incorporate a range of the types of contemporary urban development in the UK. People were asked to give a scaled score response reflecting the perceived magnitude of risk of each of a series of hazards. Each person was asked to give two responses to each hazard, one response referring to the actual present situation post-renewal and the second response referring to an imagined present situation as if renewal had not occurred. The statistical analysis of the responses suggested that urban renewal had brought about an increase in certain perceived environmental risks and not necessarily a more desirable perceived environmental state than the alternative of dereliction. 相似文献
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Economists have proved that the exclusion of the effects of irreversibility from a decision-making framework is a specification error which leads to sub-optimal solutions. Consequently, in any cost-benefit framework, the effects of an irreversibility are included in the form of an option value. Unfortunately, in the real world, there exist certain potential irreversibilities that jeopardize the very existence of the decision-making entity, were they to occur. We demonstrate that if the effects of such irreversibilities are modeled in terms of a finite option value (in cost-benefit analysis) then the optimal solutions derived therefrom may be unable to avert a potential catastrophe. In theory, an infinite option value should lead to catastrophe-averting decisions in such situations. However, in practice, such mathematical formulations tend to be intractable. In many situations, irreversible catastrophes proceed from a positive reinforcement of fluctuations in system behavior, primarily due to sympathetic responses in sub-systems. Engineers have designed relatively low-cost methods to dampen similar oscillations in physical systems. We demonstrate how such engineering type analysis can be used successfully to identify catastrophe-averting policies for a model ecosystem that faces irreversible famine that must be avoided as a precondition for survival. 相似文献
10.
Aggregation via pheromone signalling is essential for tree-killing bark beetles to overcome tree defenses and reproduce within hosts. Pheromone production is a trait that is linked to fitness, so high individual variation is paradoxical. One explanation is that the technique of measuring static pheromone pools overestimates true variation among individuals. An alternative hypothesis is that aggregation behaviour dilutes the contribution of individuals to the trait under selection and reduces the efficacy of natural selection on pheromone production by individuals. We compared pheromone measurements from traditional hindgut extractions of female southern pine beetles with those obtained by aerating individuals till they died. Aerations showed greater total pheromone production than hindgut extractions, but coefficients of variation (CV) remained high (60-182%) regardless of collection technique. This leaves the puzzle of high variation unresolved. A novel but simple explanation emerges from considering bark beetle aggregation behaviour. The phenotype visible to natural selection is the collective pheromone plume from hundreds of colonisers. The influence of a single beetle on this plume is enhanced by high variation among individuals but constrained by large group sizes. We estimated the average contribution of an individual to the pheromone plume across a range of aggregation sizes and showed that large aggregation sizes typical in mass attacks limit the potential of natural selection because each individual has so little effect on the overall plume. Genetic variation in pheromone production could accumulate via mutation and recombination, despite strong effects of the pheromone plume on the fitness of individuals within the aggregation. Thus, aggregation behaviour, by limiting the efficacy of natural selection, can allow the persistence of extreme phenotypes in nature. 相似文献