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61.
62.
Valérie?Benoit Patrick?RousseauxEmail author 《The International Journal of Life Cycle Assessment》2003,8(2):74-82
Background and Objectives Multiple Criteria Decision Aid (MCDA) methods may be employed in a great number of fields. Life Cycle Assessment (LCA) is
a specific method among the MCDA Methods. A stage of MCDA methods to be respected in LCA is the comparative evaluation of
the environmental impacts. This stage is the most difficult to implement because it is a question of estimating the global
environmental impact of the life cycles studied. To achieve this purpose, it is necessary to model the environmental impacts
and to apply a Multicriteria Analysis (MCA) method. The problem is to choose the most suitable among the available MCA methods.
The objective of this paper is to help the LCA practitioner to make this choice.
Methodology The MCA methods are compared according to their non-compensatory degree, their sensitivity to thresholds, their practicability
and their workability.
Results and Conclusion The protocol presented in this paper allows to choose the most appropriate MCA method for a given LCA according to the four
previous criteria. This choice will depend on the priorities of the decision maker with concern to the comparison criteria. 相似文献
63.
(1) Spatially explicit simulation of clonal plant growth is used to determine how ramet-level traits affect ramet density, spatial pattern of ramets and competitive ability of a clonal plant. The simulation model used combines elements of (i) an individual-based model of plant interactions, (ii) an architectural model of clonal plant growth, and (iii) a model of resource translocation within a set of physiologically integrated plant individuals. (2) The effects of two groups of parameters were studied: growth and resource acquisition parameters (resource accumulation, density-dependence of resource accumulation, resource translocation between ramets) and architectural rules (branching angle and probability of branching, internode length). The model was parameterised by values approximating those of clonally growing grasses as closely as possible. The basic parameter values were chosen from a short-turf grassland. Sensitivity analysis was carried out on relevant parameters around three basic points in the parameter space. Both single-species and two-species systems were studied. (3) It is shown that increasing resource acquisition and growth parameters increase ramet density, genet number and competitive ability. Translocation parameters and architectural parameters modify the effects of resource acquisition and growth, but their effect in single-species stands was smaller. (4) The simulations of species with fixed ramet sizes showed that ramet density in single-species stands cannot be used for predicting competitive ability. Increase in resource acquisition and growth parameters was correlated with an increase in equilibrium ramet density and competitive ability. Increasing branching angle, branching probability or internode length lead to an increased competitive ability, but did not affect equilibrium ramet density. Change of architectural parameters could therefore affect competitive ability independently of their effect on the final ramet density. (5) Spatial pattern both in single-species and two-species stands was also highly parameter-dependent. Changes in architectural parameters and in translocation usually lead to pronounced change in the spatial pattern; change in growth and resource acquisition parameters generally had little effect on spatial pattern. 相似文献
64.
An Escherichia coli mutant, ER437, which was originally isolated for colicin tolerance, was found to carry two amino acid changes in the C-terminal portion of FtsH (HflB). These mutations were demonstrated to reduce the ability of FtsH to degrade the phage lambda CII protein in vivo and in vitro, providing a rationalization for the mutant Hfl phenotype. 相似文献
65.
66.
区域农业综合生产力的AHP-Fuzzy综合评判 总被引:9,自引:0,他引:9
根据系统分析原理,在确定区域农业综合生产力系统的层次结构基础上,用层次分析法确定各因素的权重,用模糊多级综合评判法对各区域综合生产力进行综合的评价.具有一定的科学性和实用价格. 相似文献
67.
Martin Akerman Roy Noy Ron Wolchinsky Orit Izhaki Ester Schallmach Adva Kubi Naama Zabari Jacob Schachter Uri Alon Yael Mandel‐Gutfreund Michal J Besser Yoram Reiter 《Molecular systems biology》2009,5(1)
Heterogeneous cell populations form an interconnected network that determine their collective output. One example of such a heterogeneous immune population is tumor‐infiltrating lymphocytes (TILs), whose output can be measured in terms of its reactivity against tumors. While the degree of reactivity varies considerably between different TILs, ranging from null to a potent response, the underlying network that governs the reactivity is poorly understood. Here, we asked whether one can predict and even control this reactivity. To address this we measured the subpopulation compositions of 91 TILs surgically removed from 27 metastatic melanoma patients. Despite the large number of subpopulations compositions, we were able to computationally extract a simple set of subpopulation‐based rules that accurately predict the degree of reactivity. This raised the conjecture of whether one could control reactivity of TILs by manipulating their subpopulation composition. Remarkably, by rationally enriching and depleting selected subsets of subpopulations, we were able to restore anti‐tumor reactivity to nonreactive TILs. Altogether, this work describes a general framework for predicting and controlling the output of a cell mixture. 相似文献
68.
Meta-analysis in applied ecology 总被引:1,自引:0,他引:1
Gavin Stewart 《Biology letters》2010,6(1):78-81
This overview examines research synthesis in applied ecology and conservation. Vote counting and pooling unweighted averages are widespread despite the superiority of syntheses based on weighted combination of effects. Such analyses allow exploration of methodological uncertainty in addition to consistency of effects across species, space and time, but exploring heterogeneity remains controversial. Meta-analyses are required to generalize in ecology, and to inform evidence-based decision-making, but the more sophisticated statistical techniques and registers of research used in other disciplines must be employed in ecology to fully realize their benefits. 相似文献
69.
Reinout Heijungs Arjan de Koning Sangwon Suh Gjalt Huppes 《Journal of Industrial Ecology》2006,10(3):147-158
Integrated product policy, according to the European Union, requires reliable data on the impact of consumer products along their life cycles. We argue that this necessarily requires the development of an information tool for hybrid analysis, combining aspects of life-cycle assessment and input-output analysis. A number of requirements in the development of such a hybrid information tool are identified, mainly concerning data and computational structure. For the former, some important points of attention are discussed, whereas for the latter, operational formulas are developed. 相似文献
70.