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491.
Siamak Rajabi Keith W. Hipel D. Marc Kilgour 《Journal of the American Water Resources Association》2001,37(3):533-546
ABSTRACT: A new screening approach is applied to a large‐scale multiple criteria water management problem to remove actions that cannot possibly be in the best subset. An inherent advantage of the approach is its ability to identify inferior actions by examining them individually, rather than within subsets. In a case study involving the selection of actions to address high water levels in the Great Lakes‐St. Lawrence Basin, two statistical indicators, the mode and the mean, are used to aggregate the opinions of experts and representatives of interest groups on the impacts of actions according to various criteria. Application of the screening approach shows that some of the proposed actions can be removed as they can never be in the optimal subset, thereby reducing the size of the problem. 相似文献
492.
Marc Mormont 《Journal of Environmental Planning and Management》1996,39(1):131-142
River basin management is a highly complex issue, involving scientific uncertainties and competing interests between many groups. One approach is to build consensus between different users and to agree a common basis for operation. The King Baudouin Foundation in Belgium has supported the idea of 'river contracts' as a way of producing agreed strategies for river management. Examples of early contracts are described and their wider significance reviewed. 相似文献
493.
Marc Mangel 《Ecological modelling》1982,15(3):191-209
This paper is a mathematical study of the models introduced by C.W. Clark and M. Mangel to describe the tropical tuna purse seine fishery. By casting the equations into dimensionless form, it is easy to study the bifurcations of the system models and to study the dynamical behavior of the models. The dynamics are analyzed by using singular perturbation theory. A number of stochastic problems related to the dynamics of the models are formulated and solutions are obtained by using the diffusion approximation and asymptotic analysis. Finally, the question of model identification is addressed, and two methods for model identification are sketched. 相似文献
494.
Ralph Hingson Tim Heeren Thomas Mangione Suzette Morelock Marc Mucatel 《Journal of Safety Research》1982,13(1):33-38
Anonymous random digit dialing telephone surveys of nearly 6000 16–19 year old respondents were conducted in Massachusetts and Upstate New York in 1979–1981. These surveys explored frequency of driving after using marijuana, driving after drinking, respondent accident involvement in the year prior to the interview, and a variety of other respondent characteristics. Frequency of driving after using marijuana and after drinking were each associated with greater accident involvement. To isolate the accident risk of driving after marijuana use, respondents who drove after drinking were excluded from a logistic regression analysis. This analysis also controlled for the distance respondents drove and several respondent demographic characteristics. Compared to respondents who did not drive after marijuana use, teenageers who drove after smoking marijuana on at least 6 occasions per month were 2.4 times more likely to be involved in traffic accidents. Those who drove after marijuana use on at least 15 occasions per month were 2.9 times more likely to have an accident. 相似文献
495.
Marc Bekoff 《Journal of Agricultural and Environmental Ethics》1997,10(3):269-296
In this essay I argue that the evolutionary and comparative study of nonhuman animal (hereafter animal) cognition in a wide
range of taxa by cognitive ethologists can readily inform discussions about animal protection and animal rights. However,
while it is clear that there is a link between animal cognitive abilities and animal pain and suffering, I agree with Jeremy
Bentham who claimed long ago the real question does not deal with whether individuals can think or reason but rather with
whether or not individuals can suffer. One of my major goals will be to make the case that the time has come to expand. The
Great Ape Project (GAP) to The Great Ape/Animal Project (GA/AP) and to take seriously the moral status and rights of all animals
by presupposing that all individuals should be admitted into the Community of Equals. I also argue that individuals count
and that it is essential to avoid being speciesist cognitivists; it really doesn't matter whether ‘dogs ape’ or whether ‘apes
dog’ when taking into account the worlds of different individual animals. Narrow-minded primatocentrism and speciesism must
be resisted in our studies of animal cognition and animal protection and rights. Line-drawing into ‘lower’ and ‘higher’ species
is a misleading speciesist practice that should be vigorously resisted because not only is line-drawing bad biology but also
because it can have disastrous consequences for how animals are viewed and treated. Speciesist line-drawing also ignores within
species individual differences.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
496.
Since the adoption of ISO 14001, companies have examined the standard and considered certification. Although the framework is useful and enhancing environmental management systems is beneficial, the adoption of ISO 14001 alone will not provide maximum company benefits. Companies must strive for an improvement in environmental performance and financial performance that can be accomplished only through significant changes in corporate culture, structure, and systems. By developing core capabilities such as skills and knowledge, physical technical systems, managerial systems, and values and norms, companies can develop organizational learning to increase sustainable competitive advantage. This article examines how the ISO 14000 series of standards can be used to improve organizational learning and environmental management. 相似文献
497.
498.
Neilson MA Painter DS Warren G Hites RA Basu I Weseloh DV Whittle DM Christie G Barbiero R Tuchman M Johannsson OE Nalepa TF Edsall TA Fleischer G Bronte C Smith SB Baumann PC 《Environmental monitoring and assessment》2003,88(1-3):103-117
The Great Lakes Water Quality Agreement stipulates that the Governments of Canada and the United States are responsible for restoring and maintaining the chemical, physical and biological integrity of the waters of the Great Lakes Basin Ecosystem. Due to varying mandates and areas of expertise, monitoring to assess progress towards this objective is conducted by a multitude of Canadian and U.S. federal and provincial/state agencies, in cooperation with academia and regional authorities. This paper highlights selected long-term monitoring programs and discusses a number of documented ecological changes that indicate the present state of the open and nearshore waters of the Great Lakes. 相似文献
499.
Simultaneous extraction of bromide, chloride, fluoride and sulfate from soils, waste- and building materials 总被引:1,自引:0,他引:1
The simultaneous extraction of bromide, chloride, fluoride and sulfate was studied in soils, waste- and building materials. Acid, neutral and alkaline extractants were used; 0.01 mol l(-1) H(3)PO(4), milliQ-water and 0.01 mol l(-1) NaOH, respectively. The extracts were analysed by ion chromatography and ion selective electrode. Extracted concentrations were compared with the amount obtained by an alkaline smelt, as an approximation of the total extractable content. The results indicate that there is a significant difference in extraction behaviour between waste- and building materials and soils. Bromide and chloride were in general completely extracted from the former solid materials, but less than 10% and 50%, respectively, from soils. Fluoride is strongly bound in all investigated samples; less than 10% of the total content was extracted with any of the three extractants. The fraction of extracted sulfate varied between 4 and 87% of the total content, and was in general larger in waste- and building materials than in soils. Differences in extracted concentration between the 3 extractants occurred mainly for fluoride and sulfate. Extracted bromide was similar with all three extractants and extracted chloride showed differences for the various soil samples only. Increasing the NaOH concentration up to 1 mol l(-1) resulted mainly in an increase of extracted amount of fluoride and for soils also in extracted amounts of bromide and sulfate. Although, the results show that the composition of the solid material strongly influences the final pH of the extract and the extracted amount of investigated anions, application of Milli-Q water as an extractant might be a very fruitful option within the development of the Dutch Building Materials Decree. 相似文献
500.
Marc Théry 《Behavioral ecology and sociobiology》1992,30(3-4):227-237
Summary The degree to which lekking and non-lekking male manakins select display sites in order to maximise proximity to females was examined by contrasting movements of females with male dispersion. Data on female visiting patterns, male courtship disruption, and mating skew were also collected over three successive breeding seasons. For the five lek-breeding species, female home-ranges were 3–7 times larger than those of adult males. Female movements were concentrated around leks, fruiting places and stream bathing sites. None of the females monitored by radio-tracking expanded her normal range in order to visit males on leks. On the contrary, feeding bouts of females frequently preceded a visit to potential mates at neighboring leks. Despite small sample sizes, significant correlations were found between female home-range size and male clustering (distances between neighboring leks and distances between neighboring males), as predicted by the female choice model and the hotspot model. Adult and immature male home-range sizes were not significantly correlated with male dispersion or female ranges. On the other hand, males and females of the only non-lekking species exhibited similar use of space and home-range size. Male settlement at sites with high levels of female traffic showed that the hotspot model is adequate to explain differences in male dispersion among sympatric lekking species. Comparisons with other studies suggest that apparent female choice could be overidden by past and present male-male interactions or female mate-comparison tactics. In fact, both the hotspot model and the attractiveness hypothesis appear to shape male dispersion on leks: males appear to settle under hotspot conditions with despotic rules generated through bias in female choice or male-male interference. It is proposed that the evolution of leks is ecologically motivated by the spatio-temporal distribution of trophic resources, initially leading to a dispersed male-advertisement polygyny. Following this, a foraging ecology that promotes high mobility by females and the magnetic effect of mating skew in particular males may have favored clustering on exploded leks. Later, the development of male-male interference and the increasing female home-range size could have led to the evolution of classical leks. 相似文献