1,721,061 research outputs found
Statistics for the Triangle Density in ERGM and Its Mean-Field Approximation
Full text linkWe consider the edge-triangle model (also known as the Strauss model) and its mean-field approximation, within the region of parameters called replica symmetric regime. While our motivation stems from analyzing the asymptotic behavior of the triangle density in the edge-triangle model, a significant part of our work is devoted to studying an approximation of this observable in the mean-field setting, where explicit computations are possible. More specifically, for the first model, we prove that the triangle density concentrates with high probability in a neighborhood of its typical values. For the second model we can go further and prove, for the approximated triangle density, a standard and non-standard central limit theorem at the critical point, still not known for the edge-triangle model. Additionally, we obtain many concentration results derived via large deviations and statistical mechanics techniques. Although a rigorous comparison between these two models is still lacking, we believe that they are asymptotically equivalent in many respects. To support this conjectured behavior, we complement the analysis with simulations related to the central limit theorem for the edge-triangle model
Presenze femminili nella letteratura russa
No full textEurasiatica 57. Quaderni del Dipartimento di Studi Eurasiatici. Università degli Studi Ca' Foscari di Venezi
La sommessa malinconia del quotidiano negli ultimi racconti di Viktorija Tokareva
No full textEurasiatica 57. Quaderni del Dipartimento di Studi Eurasiatici. Università degli Studi Ca' Foscari di Venezi
I duchobory in Canada e Tolstoj: il momento dell'incomprensione
No full textNell'articolo sono esaminate le problematiche insorte con l'insediamento dei duchobory in Canada, soprattutto riguardo alle questioni della proprietà della terra e agli adempimenti delle registrazioni allo stato civile, alla luce delle divergenze insorte tra lo scrittore Lev Tolstoj e la guida della setta, Petr Verigin
Measurement of surface respiration: An IoT approach
Full text linkThis study investigates an approach to measuring surface gas fluxes based on the Internet of Things technology. A wireless self-powered, low-cost, low- power, cloud-connected device is designed to record humidity and carbon dioxide concentrations at multiple points. The manuscript describes the concept and reali- sation of the device, the hardware chosen and the data communication chain. The manuscript also discusses a preliminary evaluation of the performances of the pro- totype in a controlled environment, together with major strengths and limitations
WHOLE CANOPY GAS EXCHANGES AND LIGHT INTERCEPTION OF THREE PEACH TRAINING SYSTEMS
No full textCanopy photosynthesis (A(c)), transpiration (E-c) and light interception of three peach training systems, delayed vasette (DV), palmette (P), and Y-trellis (Y), were measured by a whole-canopy gas exchange open system, and a custom-built all-wave scanner-recorder, Whole-canopy assimilation rates peaked before midday in both DV and P, then A, started to decrease in the afternoon, even if light was not a limiting factor. Both canopies reached similar maximum E-c rates in late afternoon. On the contrary, A(c) of the east and west sides of the Y was nearly constant between 10:00 and 15:00 hours.In DV and P, the assimilation-transpiration ratio (ATR) decreased from early morning hours to a minimum in early afternoon, increasing thereafter. In the Y, ATR values were higher than in DV and P and, after the initial morning decrease, they remained stable until the end of the day. On a hectare base, light interception in DV and P was similar, while Y showed higher interception throughout the day. Whole-canopy photosynthesis was linearly related to the amount of light intercepted by the tree
Single leaf and whole canopy gas exchange of pear as affected by graft incompatibility
No full textLeaf and whole-canopy gas exchange of Beurré Hardy and Beurré Bosc trees, either selfrooted or grafted on clonal quince rootstocks (BA29 and MC), and a common seedling were measured to study the effect of varying degrees of graft incompatibility on tree gas exchange. Whole-canopy gas exchange was expressed in terms of the energy absorbed by the canopy, which was measured at hour intervals using a custom-built sensor. Leaf transpiration, stomatal conductance and net photosynthesis were not affected by cultivar, but they were reduced by the dwarfing quince rootstock, MC. Similar results were obtained for daily patterns of whole-canopy photosynthesis, measured in early July and August. The ratio of leaf net photosynthesis to light intercepted per tree followed the same pattern as whole-canopy photosynthesis
Simulate plants: a client-server graphic approach
No full textRecently the sector of Functional Structural Plant Modeling (FSPM) has significatively grown (AA.VV., 2004,2007) attracting the attention of researchers from several branches of biological sciences. Objective of FSP Modelers is using a morphological characterization to improve plant eco-physiological modeling. In some case they move from pure mathematical and geometrical simulators used in animation movies and landscape design, in other cases they are to interpretate external characters of a plant. Several tools has been developed, some freely downloadable, others with a commercial mean. Even when they are available at a collaborative level, the plant simulating engine is often embedded with graphics and few efforts has been made to distinguish the task of making a plant from that of representing it on a screen which also means define a standard to code plants. Communicating a virtual plant between programs with different purposes not only allow for a better use of computer resourses but could allow for plants interchange between researchers.
The development of the project required to define and reach several objectives, as the possibility to work on a virtual-plant project at a team level, with different skillness and competencies, and to define a standard language to represent plant structure separated from the geometrical features. Even if the first objective was fullfilled, it seems to require a powerful server when more clients are run at same time, as in web-games. About the second it is probably a former step toward a proposal for an open format for interchange plants at structural level. The simulator, is at present very simple and is still lacking a radiative environment. Java3D allows for self-shading but not for reciprocal shading. Other features which could be important for realistic rendering is physical collisions and gravity, both important to improve space occupation of elements parts in light and other atmospheric interactions. From the other side, the system is per se, already able to simulate a number of plants
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