Search results for "Tributi"

Adaptive consensus-based distributed detection in WSN with unreliable links

2016

Event detection is a crucial tasks in wireless sensor networks. The importance of a fast response makes distributed strategies, where nodes exchange information just with their one-hop neighbors to reach local decisions, more adequate than schemes where all nodes send observations to a central entity. Distributed detectors are usually based on average consensus, where all nodes iteratively communicate to asymptotically agree on a final result. In a realistic scenario, communications are subject to random failures, which impacts the performance of the consensus. We propose an alternative detector, which adapts to the statistical properties of the consensus and compensate deviations from the …

The probabilistic pickup-and-delivery travelling salesman problem

2019

Abstract Transportation problems are essential in commercial logistics and have been widely studied in the literature during the last decades. Many of them consist in designing routes for vehicles to move commodities between locations. This article approaches a pickup-and-delivery single-vehicle routing problem where there is susceptibility to uncertainty in customer requests. The probability distributions of the requests are assumed to be known, and the objective is to design an a priori route with minimum expected length. The problem has already been approached in the literature, but through a heuristic method. This article proposes the first exact approach to the problem. Two mathematica…

A singular elliptic equation and a related functional

2021

We study a class of Dirichlet boundary value problems whose prototype is [see formula in PDF] where 0 < p < 1 and f belongs to a suitable Lebesgue space. The main features of this problem are the presence of a singular term |u|p−2u and a datum f which possibly changes its sign. We introduce a notion of solution in this singular setting and we prove an existence result for such a solution. The motivation of our notion of solution to problem above is due to a minimization problem for a non–differentiable functional on [see formula in PDF] whose formal Euler–Lagrange equation is an equation of that type. For nonnegative solutions a uniqueness result is obtained.

On the estimation of the fatigue cycle distribution from spectral density data

1999

This paper deals with the fatigue life prediction of components and structures subjected to random fatigue, i.e. to cyclic loading whose amplitude varies in an essentially random manner. In particular, this study concentrates on the general problem of directly relating fatigue cycle distribution to the power spectral density (PSD) by means of closed-form expressions that avoid expensive digital simulations of the stress process. At present, all the methods proposed to achieve this objective are based on the use of a single parameter of the PSD. In this work, by numerical simulations and theoretical considerations, it is shown that the statistical distribution of fatigue cycles depends on f…

VARIABLE SELECTION FOR NOISY DATA APPLIED IN PROTEOMICS

2014

International audience; The paper proposes a variable selection method for pro-teomics. It aims at selecting, among a set of proteins, those (named biomarkers) which enable to discriminate between two groups of individuals (healthy and pathological). To this end, data is available for a cohort of individuals: the biological state and a measurement of concentrations for a list of proteins. The proposed approach is based on a Bayesian hierarchical model for the dependencies between biological and instrumental variables. The optimal selection function minimizes the Bayesian risk, that is to say the selected set of variables maximizes the posterior probability. The two main contributions are: (…

Outward Investments and Productivity: Evidence from European Regions

2016

Castellani D. and Pieri F. Outward investments and productivity: evidence from European regions, Regional Studies. Using a novel data set on international investment projects, this paper builds measures of outward foreign direct investments (FDIs) for 262 regions of the European Union. This allows as estimation to be made of regressions of productivity growth over the 2007–11 period as a function of the number of FDIs. The number of outward FDIs in manufacturing activities is negatively associated with productivity growth in the home region, but investments in sales, distribution and marketing are associated with a boost in local productivity. This is driven especially by investments toward…

Conditional Versus Joint Probability Assessments

1984

AbstractThe assessment of conditional and / or joint probabilities of events that constitute scenarios is necessary for sound planning, forecasting, and decision making. The assessment process is complex and subtle, and various difficulties are encountered in the elicitation of such probabilities such as, implicit violations ofthe probability calculus and some meaningfjilness conditions. The necessary and sufficient as well as meaningfulness conditions that the elicited information on conditional and joint probabilities must satisfy are evaluated against actual assessments empirically. A high frequency of violation of these conditions was observed in assessing both conditional and joint pro…

2019

Final disposal of spent nuclear fuel (SNF) from nuclear power plants (NPPs) is an ethical issue with implications within and across generations. We address this issue from the perspective of nuclear communities that host nuclear waste disposal sites. These are primarily the communities that face injustice due to the potential radiological risks. A resident survey (n = 454) was conducted in two Finnish nuclear communities, i.e. Eurajoki and Pyhajoki, that are being considered as alternative sites for a second repository for SNF. The nuclear waste management (NWM) company Posiva is already building a repository in Eurajoki, the first in Finland. These communities are in different stages of th…

A Mechanical Approach for Evaluating the Distribution of Confinement Pressure in FRP-Wrapped Rectangular Columns

2019

In recent decades, fiber reinforced polymer (FRP) wrapping has become a common technique to retrofit reinforced concrete (RC) columns. Numerous research works have sought to verify analytically and experimentally its effectiveness in terms of enhancement of axial load bearing capacity and ductility. These studies highlighted that in the case of sharp-cornered sections, the maximum allowable confinement pressure is limited by premature failure at corners and, consequently, stress in the FRP, as well as the distribution of the confinement pressure, is not uniform. The prediction of this phenomenon is not straightforward, and existing theoretical studies propose complex numerical simulations, …

Two novel subjective logic-based in-network data processing schemes in wireless sensor networks

2016

Wireless sensor networks (WSNs) consist of connected low-cost and small-size sensor nodes. The sensor nodes are characterized by various limitations, such as energy availability, processing power, and storage capacity. Typically, nodes collect data from an environment and transmit the raw or processed data to a sink. However, the collected data contains often redundant information. An in-network processing scheme attempts to eliminate or reduce such redundancy in sensed data. In this paper, we propose two in-network data processing schemes for WSNs, which are built based on a lightweight algebra for data processing. The schemes bring also benefits like decreased network traffic load and inc…