Search results for "Tree"
showing 10 items of 1841 documents
Operational and financial effectiveness of e-collaboration tools in supply chain integration
2004
This paper develops a comprehensive model of supply chain integration and uses it to analyze and assess the operational and financial effectiveness of different e-collaboration tools at various levels of supply chain integration. This model is also used to evaluate the importance of the sequence in which e-collaboration tools are adopted in supply chain integration. Computational results from a validated system dynamics simulation model with different implementation sequences of e-collaboration tools and different financial scenarios show that local financial constraints can also severely impact operational and financial performance of the entire supply chain. (C) 2003 Elsevier B.V. All rig…
Unraveling the evolutionary history of the phosphoryl-transfer chain of the phosphoenolpyruvate:phosphotransferase system through phylogenetic analys…
2007
[Background] The phosphoenolpyruvate phosphotransferase system (PTS) plays a major role in sugar transport and in the regulation of essential physiological processes in many bacteria. The PTS couples solute transport to its phosphorylation at the expense of phosphoenolpyruvate (PEP) and it consists of general cytoplasmic phosphoryl transfer proteins and specific enzyme II complexes which catalyze the uptake and phosphorylation of solutes. Previous studies have suggested that the evolution of the constituents of the enzyme II complexes has been driven largely by horizontal gene transfer whereas vertical inheritance has been prevalent in the general phosphoryl transfer proteins in some bacter…
A genetic algorithm for image segmentation
2002
The paper describes a new algorithm for image segmentation. It is based on a genetic approach that allow us to consider the segmentation problem as a global optimization problem (GOP). For this purpose, a fitness function, based on the similarity between images, has been defined. The similarity is a function of both the intensity and the spatial position of pixels. Preliminary results, obtained using real images, show a good performance of the segmentation algorithm.
Evolution of Leaf Morphogenesis: Evidence from Developmental and Phylogenetic Data in Papaveraceae
1999
Variation of leaf morphology in Papaveraceae s.l. (including Fumariaceae and Pteridophyllum) has previously been shown to be related to developmental differences in the direction of segmentation and in blade‐petiole differentiation. Based on ontogenetic comparisons, we here distinguish polyternate, acropetal, basipetal‐pedate, basipetal‐pinnate, and divergent modes of dissection. In addition, undissected leaves occur in some taxa. Dissection modes can be grouped in two classes on the basis of blade‐petiole differentiation. Mapping of these morphogenetic traits on an independently obtained phylogenetic reconstruction reveals a high degree of homoplasy, indicating multiple evolutionary parall…
Behavior adaptation and selection.
2010
6 pages; The evolutionary approach to behavior is concerned with the evolutionary origin and adaptive function of behavioral traits. Like any other part of the phenotype, behavior can be shaped by natural selection to produce adaptations. However, behavior often shows large phenotypic variation and flexibility, and can be both – subject to selection and a major agent of selection. Therefore, the study of adaptation and evolution of behavior is a particularly complex one, involving a wide range of methodologies and techniques, including mathematical modeling, comparative methods, phenotypic engineering, quantitative genetics, genetic dissection, and artificial selection.
Coherent destruction of tunneling in a six-dimensional model of NHD2: a computational study using the multi-configuration time-dependent Hartree meth…
2014
We investigate the phenomenon of coherent destruction of tunneling in a six-dimensional model of the NHD2 molecule. Two regimes are considered for the frequency of the laser field. A non-resonant regime where the frequency of the laser field is high with respect to the ground vibrational state tunneling splitting but smaller than the transition frequencies between the ground and excited vibrational states; and a quasi-resonant regime where the frequency of the laser field is close to the transition frequency between the ground and first excited vibrational states. In each case, we study the laser driven dynamics in the framework of the Floquet formalism and derive simple analytical formulas…
Asian relationships of the flora of the European Alps
2008
Background: It has long been recognised that the Alps have strong biogeographical links to Asia. Aims: We investigate here whether the two areas are connected either through southern (mountain chains between the Alps and the Himalayas) or through northern regions. Methods: We compiled the geographical distribution of plant genera growing both in the Alps and the Himalayas, and outside these two regions. This compilation was used to search for molecular phylogenetic literature which was screened for area relationships informative for our purposes. Results: Of 933 genera growing in the Alps, 653 were considered further. Of the 429 genera growing in the Alps and the Himalayas, 218 grow in both…
Non-Waste Technology for Utilization of Tree Branches
2022
The trees (e.g., fruit or decorative) growing on the homestead plots of private households provide opportunities for sustainable biomass obtained from pruned branches every year. Profitable production of fuel material requires high-performance equipment and methods by which wood chips can be produced at low cost. The practice of chopping tree branches shows that not all chopping machines are suitable for use on homestead plots. This research gives the five-year test results of a developed and patented tree branch chopping machine under special operating conditions. The machine was tested under the conditions of the homestead plot of a private household in the Poltava region, and the enginee…
Novel leaf-level measurements of chlorophyll fluorescence for photosynthetic efficiency
2015
Solar induced chlorophyll fluorescence (SIF) from vegetation can now be obtained from satellites as well as ground-based field studies, at select wavelengths associated with atmospheric features. At the leaf level, full spectrum (650–800 nm) chlorophyll emissions (ChlF) can be measured using specialized instrumentation to support interpretation of these SIF observations. We found that ChlF spectra differ for leaf bottoms versus upper leaf surfaces, potentially affecting within-canopy radiative scattering. Our ChlF measurements for leaves of eight tree species (n≥125) obtained during fall 2013 senescence at the Duke Forest in North Carolina, USA and the 2014 growing season (n=72) at the USDA…
On Applying Adaptive Data Structures to Multi-Player Game Playing
2013
In the field of game playing, the focus has been on two-player games, such as Chess and Go, rather than on multi-player games, with dominant multi-player techniques largely being an extension of two-player techniques to an \(N\)-player environment. To address the problem of multiple opponents, we propose the merging of two previously unrelated fields, namely those of multi-player game playing and Adaptive Data Structures (ADS). We present here a novel move-ordering heuristic for a dominant multi-player game playing algorithm, namely the Best-Reply Search (BRS). Our enhancement uses an ADS to rank the opponents in terms of their respective threat levels to the player modeled by the AI algori…