Search results for " value"

Project monitoring by dynamic statistical control charts

2020

Project monitoring activities are fundamental to assure a timely identification of unacceptable project's deviations from the baseline, so that corrective actions may be taken to bring the project back in line with its objectives. Regarding this, the most used approach is the Earned Value Management (EVM) technique. However, traditional EVM metrics do not allow the Project Manager (PM) to recognize if project deviations are due to the natural project variability or to systemic and undiscovered causes that are moving the project to unacceptable out-of-controls. With this recognition, a statistical project control system based on the use of dynamic Shewhart's and CUmulative SUM (CUSUM) contro…

Formation of high added value chemicals by photocatalytic treatment of biomass

2020

The depletion of fossil fuel requires the search for alternative renewable feedstock and environmentally friendly methods for the production of high value-added compounds and fuels. In this context, the efficient use of biomass has emerged as a significant research field as it represents an alternative green and renewable carbon source. Various technologies have been explored for this purpose and heterogeneous photocatalysis represents a valid alternative to the catalytic methods since it can be carried out under mild experimental conditions without the addition of harmful oxidizing agents. Different biomass components have been used as the starting materials, and many valuable chemicals h…

Solar heterogeneous photocatalysis for high added value molecules production

A facile way to synthesize noble metal free TiO2 based catalysts for glycerol photoreforming

2023

In this work anaerobic heterogeneous photocatalytic solar/UV light reforming of glycerol in aqueous media was performed with Pt-photodeposition and noble metal free modified TiO2 photocatalysts prepared through ball milling, a very simple and cheap coupled catalyst preparation method. Different amounts of Cu2O or 3% CuO were loaded on TiO2 using ball milling and during each run glycerol conversion, hydrogen and CO2 formed in the gas phase and 1,3-dihydroxyacetone (DHA) and glyceraldehyde (GA) in the liquid phase were determined. The results were compared with the aim to verify the effectiveness of Cu2O in replacing Pt. Using noble metal free photocatalysts, 33% glycerol conversion, 10.3% an…

Vibration-based identification of mechanical properties of orthotropic arbitrarily shaped plates: Numerical and experimental assessment

2018

Abstract An innovative procedure is introduced for the identification of the mechanical parameters of orthotropic plates of arbitrary shape, under various boundary conditions, based on vibration data. The method employs a combination of a convenient Rayleigh-Ritz approach and Particle-Swarm Optimization to estimate elastic constants of the orthotropic material in a straightforward manner, without requiring computationally demanding iterative Finite Element analyses. Specifically, the pb-2 Rayleigh-Ritz procedure is extended and applied to deal with orthotropic plates, simplifying the approach to more easily treat generic plate shapes, taking advantage of the Green's theorem. The method is t…

Economic impact of Ice Thermal Energy Storage Systems in residential buildings in presence of double-tariffs contracts for electricity

2009

Thermal energy storage is one of the most important methods of demand-side load management, thanks to the capacity of reducing significantly the peak power demand for air conditioning in buildings. Thermal Energy Storage Systems (TESS) are indeed used for producing and storing cooling capacity during off-peak hours (in particular during night hours) to meet the following day's air conditioning requirements. The current paper presents a study on the effects of the installation of Ice TESS for cooling on the power daily profile of residential buildings, and examines the economic repercussions on the electricity billing. With reference to this second theme, the paper examines, in particular, t…

Rateless Codes Performance Analysis in Correlated Channel Model for GEO Free Space Optics Downlinks

2012

Smart Auctions for Autonomic Ambient Intelligence Systems

2020

The main goal of Ambient Intelligence (AmI) is to support users in their daily activities by satisfying and anticipating their needs. To achieve such goal, AmI systems rely on physical infrastructures made of heterogenous sensing devices which interact in order to exchange information and perform monitoring tasks. In such a scenario, a full achievement of AmI vision would also require the capability of the system to autonomously check the status of the infrastructure and supervise its maintenance. To this aim, in this paper, we extend some previous works in order to allow the self-management of AmI devices enabling them to directly interact with maintenance service providers. In particular,…

A Knowledge Management System using Bayesian Network

2009

In today's world, decision support and knowledge management processes are strategic and interdependent activities in many organizations. The companies' interest on a correct knowledge management is grown, more than interest on the mere knowledge itself. This paper proposes a Knowledge Management System based on Bayesian networks. The system has been tested collecting and using data coming from projects and processes typical of ICT companies, and provides a Document Management System and a Decision Support system to share documents and to plan how to best use firms' knowledge.

TSVD as a Statistical Estimator in the Latent Semantic Analysis Paradigm

2015

The aim of this paper is to present a new point of view that makes it possible to give a statistical interpretation of the traditional latent semantic analysis (LSA) paradigm based on the truncated singular value decomposition (TSVD) technique. We show how the TSVD can be interpreted as a statistical estimator derived from the LSA co-occurrence relationship matrix by mapping probability distributions on Riemanian manifolds. Besides, the quality of the estimator model can be expressed by introducing a figure of merit arising from the Solomonoff approach. This figure of merit takes into account both the adherence to the sample data and the simplicity of the model. In our model, the simplicity…