8,942 research outputs found
Distributed Adaptive Learning of Graph Signals
The aim of this paper is to propose distributed strategies for adaptive
learning of signals defined over graphs. Assuming the graph signal to be
bandlimited, the method enables distributed reconstruction, with guaranteed
performance in terms of mean-square error, and tracking from a limited number
of sampled observations taken from a subset of vertices. A detailed mean square
analysis is carried out and illustrates the role played by the sampling
strategy on the performance of the proposed method. Finally, some useful
strategies for distributed selection of the sampling set are provided. Several
numerical results validate our theoretical findings, and illustrate the
performance of the proposed method for distributed adaptive learning of signals
defined over graphs.Comment: To appear in IEEE Transactions on Signal Processing, 201
Determination of hidden variable models reproducing the spin-singlet
The experimental violation of Bell inequality establishes necessary but not
sufficient conditions that any theory must obey. Namely, a theory compatible
with the experimental observations can satisfy at most two of the three
hypotheses at the basis of Bell's theorem: free will, no-signaling, and
outcome-Independence. Quantum mechanics satisfies the first two hypotheses but
not the latter. Experiments not only violate Bell inequality, but show an
excellent agreement with quantum mechanics. This fact restricts further the
class of admissible theories. In this work, the author determines the form of
the hidden-variable models that reproduce the quantum mechanical predictions
for a spin singlet while satisfying both the hypotheses of free will and
no-signaling. Two classes of hidden-variable models are given as an example,
and a general recipe to build infinitely many possible models is provided.Comment: Slightly revised version, 7 pages, no figures, to appear in PRA.
Final version, removed extra references no longer cite
Patterns of variability in early life traits of a Mediterranean coastal fish
Spawning dates and pelagic larval duration (PLD) are early life traits (ELT) crucial for understanding life cycles, properly assessing patterns of connectivity and gathering indications about patchiness or homogeneity of larval pools. Considering that little attention has been paid to spatial variability in these traits, we investigated variability of ELT from the analysis of otolith microstructure in the common two-banded sea bream Diplodus vulgaris. In the southwestern Adriatic Sea, along ~200 km of coast (âŒ1° in latitude, 41.2° to 40.2°N), variability of ELT was assessed at multiple spatial scales. Overall, PLD (ranging from 25 to 61 d) and spawning dates (October 2009 to February 2010) showed significant variability at small scales (i.e. <6 km), but not at larger scales. These outcomes suggest patchiness of the larval pool at small spatial scales. Multiple causal processes underlying the observed variability are discussed, along with the need to properly consider spatial variability in ELT, for example when delineating patterns of connectivity. Copyright © 2013 Inter-Research
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Pension schemes versus real estate
The demographic, economic and social changes that have characterized the last decades, and the dramatic financial crisis that has taken place since 2008, have led to a demand for structural changes in the pension sector and a growing interest in individual pension products. Hence the need, for most elderly people, to liquidate their fixed assets, which are usually the homes in which they live. This highlights products such as reverse mortgages and domestic reversibility plans. Within this context, we propose a contractual scheme where an immediate life annuity is obtained by paying a single-premium in the form of real estate rights (RERs), for example by transferring to an insurer the property title of a house or a similar realty, while keeping its usufruct or a restricted bundle of rights. The level of the installments depends on the fair value of the transferred RER at the contractâs issue, the life expectancy of the insured and the expected growth rate of the real estate market value. The contract design is developed by considering the control of the financial risk inherent in the contract itself, because of the prospective changes in the value of the RERs, and the level of the insurerâs leverage. Finally, we provide some numerical evidence of the proposed contractual structure, in order to compare the level of the installments according to the house return forecasts in different European countries
Recupero e consolidamento della collezione scheletrica del Museo di Zoologia âDoderleinâ
Il presente articolo illustra unâoperazione di restauro che ha aperto una fase di recupero di diversi elementi scheletrici, da tempo deteriorati, nel Museo di Zoologia âDoderleinâ, oggi afferente al Sistema Museale dâAteneo - SIMUA - dellâUniversitĂ degli Studi di Palermo. Il lavoro si Ăš articolato in pulitura, restauro e consolidamento di cinquanta pezzi dei cinque gruppi di vertebrati. Questo intervento rappresenta solamente una piccola tessera di un progetto piĂč ampio, che ha come obiettivo finale il recupero dellâintera collezione zoologica presente in Museo.The present work took place in the Museum of Zoology âDoderleinâ of the SIMUA, University of Palermo. A restoration of skeletons was performed following the main phases: cleaning, restoration and consolidation of fifty pieces of the main five vertebrate taxa. This action represents the beginning of a wider project, of which the final aim is to recover the entire zoological collection present in the Museum
Evaluation of graft success of grapevine after incubation room by means of thermographic, electrical and mechanical techniques
Grafting is an important technique for getting good yields in plant multiplication. Understanding the success of the graft after the incubation stage is important to the evaluation of the suitable grafting for the open field (nursery). Successful grafting in vines requires the development of a functional vascular system between the scion and the rootstock. The graft compatibility and its augmentation depend upon various natural factors like environment, soil conditions and protective measures. The present study examines the capability of thermographic, mechanical and electrical techniques to assess the graft quality and success after the incubation stage. The trial was carried out at Vivai Mannone, (Petrosino, Western Sicily, 37\uc2\ub042'26.28''N - 12\uc2\ub029'09.57''E). After the different tests, various grafting combinations were planted in the nursery and followed for the vegetative season. Before the evaluation procedure was performed graft unions have been subjected to a moderate heating from ambient temperature, then the thermal transient toward ambient temperature was monitored by means of a thermal imaging camera. As far as the electrical testing procedure was concerned, a sinusoidal voltage was applied through the grafts-cuttings, and the voltage attenuation at different points at increasing distances from the source was measured by an oscilloscope. The mechanical strength of the graft undergoing a controlled rate flexural loading was monitored by a PC remote controlled digital dynamometer. Experimental results show that we were able to distinguish the successful grafting only with the thermographic test. Moreover, this technique was the only non-destructive test from which it was possible to derive quantitative parameters, useful to provide successful nursery forecast. Engraftment results detected at the nursery showed a 15% error in forecast based on the proposed thermal image method, which is a satisfactory value for a feasibility study
Erratum to: Indirect land use changes of biofuel production â a review of modelling efforts and policy developments in the European Union
Botanicals in Functional Foods and Food Supplements: Tradition, Efficacy and Regulatory Aspects
In recent decades, the interest in products containing botanicals and claiming \u201cfunctional\u201d properties has increased exponentially. Functional foods, novel foods and food supplements have a special impact on the consumers, who show significant expectation for their well-being. Food supplements with botanical ingredients are the food area that has witnessed the greatest development, in terms of the number of available products, budget, and consumer acceptability. This review refers to and discusses some open points, such as: 1) the definitions and regulation of products containing botanicals; 2) the difficulty in obtaining nutritional and functional claims (botanical ingredients obtaining claims in the EU are listed and summarized); 3) the safety aspects of these products; and 4) the poor harmonization between international legislations. The availability of these "new" products can positively influence the well-being of the population, but it is essential to provide the consumers with the necessary recommendations to guide them in their purchase and use
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