2,000 research outputs found
Commentary: Estimating the global conservation status of more than 15,000 Amazonian tree species
Alien Registration- Feeley, Michael J. (Portland, Cumberland County)
https://digitalmaine.com/alien_docs/31837/thumbnail.jp
Alien Registration- Feeley, Michael J. (Portland, Cumberland County)
https://digitalmaine.com/alien_docs/31837/thumbnail.jp
Many species risk mountain top extinction long before they reach the top
Analyses of topography show that mountains do not monotonically decrease in area with elevation as is commonly believed and that in reality land area often increases at higher elevations. This finding bodes well for the future of biodiversity since it means that in many parts of the world there are sufficient upslope areas for low- and mid-elevation species to migrate into as temperatures increase. However, more attention needs to be given to determining if migrating species can actually reach these expansive high-elevation areas. Many factors can prevent species from migrating upslope including stable ecotones. Often ecotonal boundaries are not set by mean temperatures alone and thus are not shifting upslope with warming. An example of this are tropical alpine treelines, which are not shifting upslope despite rapid warming potentially due to the stabilizing influences of climatic factors other than mean temperatures (e.g., extreme cold events) or non-climatic factors (e.g., soil or human disturbances). Stable ecotones can potentially prevent species from expanding their ranges into upland areas in which case the amount of land at higher elevations is irrelevant and species may face “mountain top extinctions” long before they reach the actual tops of the mountains
Parallel optimization algorithms and their implementation in VLSI design
Two new parallel optimization algorithms based on the simplex method are described. They may be executed by a SIMD parallel processor architecture and be implemented in VLSI design. Several VLSI design implementations are introduced. An application example is reported to demonstrate that the algorithms are effective
Automated Data Management Information System (ADMIS)
ADMIS stores and controls data and documents associated with manned space flight effort. System contains all data oriented toward a specific document; it is primary source of reports generated by the system. Each group of records is composed of one document record, one distribution record for each recipient of the document, and one summary record
A new eddy current model for magnetic bearing control system design
This paper describes a new VLSI-based controller for the implementation of a Linear-Quadratic-Gaussian (LQG) theory-based control system. Use of the controller is demonstrated by design of a controller for a magnetic bearing and its performance is evaluated by computer simulation
Where are the tropical plants? A call for better inclusion of tropical plants in studies investigating and predicting the effects of climate change
Tropical plant species are systematically underrepresented in large-scale analyses or synthesis looking at the potential effects of global climate change. The reason being that we simply don’t know enough about the distributions and ecologies of most tropical plant species to predict their fate under climate change. This gaping hole in our knowledge is extremely worrisome given the high diversity of tropical plants, the crucial roles that they play in supporting global diversity and ecosystem function, and the elevated threats that climate change may pose to tropical species in general. </p
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