Theoretical studies of process flexibility designs had mostly focused on average-case analysis. In this paper, we take a different approach by studying process flexibility designs from a worst-case point of view. To study the worst-case performances, we introduce the so-called plant cover index, an index defined by a constrained bipartite vertex cover problem associated with a given flexibility...

The performance of many desert plant species in North America may decline with the warmer and drier conditions predicted by climate change models, thereby accelerating land degradation and reducing ecosystem productivity. We paired repeat measurements of plant canopy cover with climate at multiple sites across the Chihuahuan Desert over the last century to determine which plant species and func...

introduction amount and vertical distribution of leaf area are essential for estimating interception and utilization of solar radiation of crop canopies and, consequently dry matter accumulation (valentinuz & tollenaar, 2006). vertical distribution of leaf area is leaf areas per horizontal layers, based on height (boedhram et al., 2001). above-ground biomass is one of the central traits in func...

For an optimum use of natural resources in the sustainable development trend, there is a need to identify ecological resources in the shortest period of time and minimum possible cost. In this article, we aimed Management ecosystem by Assessment of plant covers changes at Taleghan Township in a twenty year period. Percentage of landscape and number of patch were among the metrics that were calc...

An intense debate exists on the effects of post-fire salvage logging on plant community regeneration, but scant data are available derived from experimental studies. We analyzed the effects of salvage logging on plant community regeneration in terms of species richness, diversity, cover, and composition by experimentally managing a burnt forest on a Mediterranean mountain (Sierra Nevada, S Spai...

Abstract Soil, is a reclamable and sustainable source. it is the basis of survival and it’s implication, should be performed on the basis of productivity identification according to scientific and technical rules, we can protect this valuable source, and increase it’s productivity and usage. Nowdays, saline soils cover nearly 14.6% of the country area. Study areas (Kashan’ playa) have saline ...