Tagliafico A.,Italian National Cancer Institute |
Tagliafico G.,Genova Engineering, LLC. |
Martinoli C.,University of Genoa
Ultrasound in Medicine and Biology | Year: 2010
The possibility to realize a quantitative evaluation of nerve density on ultrasound is clinically important to enhance the evaluation of peripheral nerve disorders. We developed software that quantifies the ratio between the hypoechoic and hyperechoic areas of peripheral nerves on ultrasound. Nerve density was defined as (hypoechoic pixels)/(total pixels) and the purpose of our study was to asses if nerve density can be used to differentiate pathologic conditions affecting peripheral nerves. Ultrasound images of peripheral nerves were obtained with a high-frequency probe (17-5 MHz, 288 elements). Sixty-five different patients and (n = 65) controls (age range, 35-81 years; mean 55 years) were prospectively evaluated. Thirty-five patients had carpal tunnel syndrome and 30 patients had neurofibromas. Three radiologists performed a semiautomated evaluation with intra and interobserver agreement. A complete automatic evaluation was performed with no need of intra and interobserver evaluation. With the semiautomated evaluation, mean intraobserver agreement was good (K = 0.85). Interobserver agreements was good as well (reader 1 vs reader 2: k = 0.72; reader 2 vs reader 3: k = 0.80; reader 3 vs reader 1: k = 0.72). Differences among value of nerve density in normal nerves, CTS and neurofibromas were statistically significant (p < 0.0001). There were no statistically significant differences between the results obtained using the automatic or the semiautomatic method. Nerve density is capable of discriminating between normal and pathologic nerves of patients affected by carpal tunnel syndrome or neurofibromas. Moreover, nerve density measure is useful to discriminate between patients with mild and severe CTS. (E-mail: email@example.com). © 2010 World Federation for Ultrasound in Medicine & Biology.
Reverberi A.P.,DCCI |
Fabiano B.,Genova Engineering, LLC. |
International Communications in Heat and Mass Transfer | Year: 2013
We propose a method for the estimation of the overall heat transfer coefficient to/from a fluid in a cylindrical pipe at high Peclet numbers from/to a medium with unknown temperature profile in the axial direction. The method uses an analytical solution of the heat equation in cylindrical coordinates subject to a Robin boundary condition and a parametrised, piecewise linear approximation of the external temperature profile. The velocity profiles of both viscous and turbulent flows are considered and compact solutions of the temperature profile of the fluid are evaluated in both cases as functions of the heat transfer coefficient and of the unknown external temperature profile.It is shown that these solutions provide an efficient method for the estimation of the heat transfer coefficient from fluid temperature data based on separable least squares. The overall procedure is illustrated by a numerical example using simulated data. © 2012 Elsevier Ltd.
Tagliafico G.,Genova Engineering, LLC. |
Scarpa F.,Genova Engineering, LLC. |
Canepa F.,University of Genoa
International Journal of Refrigeration | Year: 2010
Active Magnetic Regeneration (AMR) is a configuration that allows magnetic refrigeration to be suitable also for room temperature applications. This work is intended to detect, by means of a 1-D numerical model, the influence on the regenerator performances of the working condition ambient temperature (TCURIE ± 20 K) and of the operating parameters fluid mass flow rate (utilization factor 0.5÷3.5) and cycle frequency (0.1÷0.6 Hz). Simulations show that, tuning the fluid mass flow rate, a gadolinium AMR (395 g, f = 0.25 Hz, ΔB = 1.7 T) can reach a maximum cooling capacity of 130 W and a 40 W cooling power over a temperature span of 30 K. A COP of 5 can also be achieved with a temperature span of 30 K and a cooling power of 35 W. Frequency has a weak influence on the AMR's COP, while the ambient temperature is crucial. The system loses the 60% of cooling capacity if the ambient temperature is 20 K away from the material Curie temperature. © 2009 Elsevier Ltd and IIR.
Alessandri A.,Genova Engineering, LLC. |
Baglietto M.,niversity of Genoa |
Battistelli G.,University of Florence
Automatica | Year: 2010
State estimation is addressed for a class of discrete-time systems that may switch among different modes taken from a finite set. The system and measurement equations of each mode are assumed to be linear and perfectly known, but the current mode of the system is unknown. Moreover, additive, independent, normally distributed noises are assumed to affect the dynamics and the measurements. First, relying on a well-established notion of mode observability developed "ad hoc" for switching systems, an approach to system mode estimation based on a maximum-likelihood criterion is proposed. Second, such a mode estimator is embedded in a Kalman filtering framework to estimate the continuous state. Under the unique assumption of mode observability, stability properties in terms of boundedness of the mean square estimation error are proved for the resulting filter. Simulation results showing the effectiveness of the proposed filter are reported. © 2010 Elsevier Ltd. All rights reserved.
Bolla R.,Genova Engineering, LLC. |
Bruschi R.,University of Genoa |
Carrega A.,Genova Engineering, LLC. |
Davoli F.,Genova Engineering, LLC.
IEEE/ACM Transactions on Networking | Year: 2014
With the aim of controlling power consumption in metro/transport and core networks, we consider energy-aware devices able to reduce their energy requirements by adapting their performance. In particular, we focus on state-of-the-art packet processing engines, which generally represent the most energy-consuming components of network devices, and which are often composed of a number of parallel pipelines to 'divide and conquer' the incoming traffic load. Our goal is to control both the power configuration of pipelines and the way to distribute traffic flows among them. We propose an analytical model to accurately represent the impact of green network technologies (i.e., low power idle and adaptive rate) on network- and energy-aware performance indexes. The model has been validated with experimental results, performed by using energy-aware software routers loaded by real-world traffic traces. The achieved results demonstrate how the proposed model can effectively represent energy- and network-aware performance indexes. On this basis, we propose a constrained optimization policy, which seeks the best tradeoff between power consumption and packet latency times. The procedure aims at dynamically adapting the energy-aware device configuration to minimize energy consumption while coping with incoming traffic volumes and meeting network performance constraints. In order to deeply understand the impact of such policy, a number of tests have been performed by using experimental data from software router architectures and real-world traffic traces. © 2013 IEEE.
Panizza M.,Genova Engineering, LLC. |
Delucchi M.,Genova Engineering, LLC. |
Sires I.,University of Barcelona
Journal of Applied Electrochemistry | Year: 2010
In this paper, the anodic oxidation of a real leachate from an old municipal solid waste landfill has been studied using an electrolytic flow cell equipped with a lead dioxide (PbO2) anode and stainless steel as the cathode. The influence of several operation parameters such as (i) the applied current (from 0.5 to 3 A), (ii) liquid flow rate (from 50 to 420 L h -1), (iii) temperature (from 25 to 50 °C), and (iv) pH (from 3.5 to 8.2) on the COD removal rate, current efficiency, and energy consumption has been evaluated. The galvanostatic electrolyses always yielded COD values below the discharge limit (COD <160 mg L-1); the COD removal rate increased with rising applied current, solution pH, and temperature, whereas it remained almost unaffected by the recirculation flow rate. These results indicate that the organic compounds were mainly removed by their indirect oxidation by the active chlorine generated from chlorides oxidation. The specific energy consumption necessary to reduce the organic load to below the disposal limit was 90 kWh m-3. © 2010 Springer Science+Business Media B.V.
Storace M.,Genova Engineering, LLC. |
Poggi T.,Genova Engineering, LLC.
International Journal of Circuit Theory and Applications | Year: 2011
Digital architectures for the circuit realization of multivariate piecewise-linear (PWL) functions are reviewed and compared. The output of the circuits is a digital word representing the value of the PWL function at the n-dimensional input. In particular, we propose two architectures with different levels of parallelism/complexity. PWL functions with n = 3 inputs are implemented on an FPGA and experimental results are shown. The accuracy in the representation of PWL functions is tested through three benchmark examples, two concerning three-variate static functions and one concerning a dynamical control system defined by a bi-variate PWL function. © 2009 John Wiley & Sons, Ltd.
Bracco S.,Genova Engineering, LLC. |
Delfino F.,Genova Engineering, LLC. |
Pampararo F.,Genova Engineering, LLC. |
Robba M.,Genova Engineering, LLC. |
Rossi M.,Genova Engineering, LLC.
Renewable and Sustainable Energy Reviews | Year: 2013
Nowadays, as set by the EU 20-20-20 targets, the reduction of primary energy use and greenhouse gas emissions in the energy sector can be attained by increasing the use of renewable sources and improving energy efficiency. Many national and international research programs are aiming at developing innovative technologies and new energy management strategies in order to reach the targets set out in the 20-20-20 directive. In this context, a primary role is played by the Distributed Generation (DG), which refers to the electrical and thermal generation located near to the place of use, exploiting available renewable sources. One of the best way to exploit the emerging potential of DG is to take a system approach which views generation and associated loads as a whole concept called microgrid. The sources can operate in parallel to the grid or can operate in island, providing utility power station services. Utilization of waste heat from the sources will increase total efficiency, making the polygeneration microgrid more financially attractive and smart from the energy consumption standpoint. The smartness is also in the management system, where control strategies aiming at the optimization of technical, economical and environmental issues are typically implemented. This paper deals with smart microgrids, addressing basically the following topics: (1) to review methods, models, tools, technologies and research challenges in the specific field; (2) to present the University of Genoa Smart Polygeneration Microgrid (SPM), built with the financial contribution of the Italian Ministry of Education, University and Research at the decentralized Savona Campus facilities. The SPM produces energy at low emissions for the University and operates as a test-bed facility for research, testing and development of smart grid components. © 2012 Elsevier Ltd. All rights reserved.
Finocchio E.,Genova Engineering, LLC. |
Lodi A.,Genova Engineering, LLC. |
Solisio C.,Genova Engineering, LLC. |
Converti A.,Genova Engineering, LLC.
Chemical Engineering Journal | Year: 2010
Biosorption of heavy metals is an interesting approach to treat industrial wastewaters by an environmentally friendly system. Spirulina platensis biomass, an effective biosorbent for cations, cannot be used to adsorb chromate due to its negatively charged surface close to neutral conditions; therefore, methylation of biomass was performed to increase its adsorption capacity under these conditions. Batch adsorption tests carried out varying both Cr(VI) and methylated biomass concentrations showed that 2-4 g l-1 of biosorbent were able to remove Cr(VI) with efficiency ≥80%, while higher Cr(VI) levels (43-50 mg l-1) showed low removal efficiency. The model of Langmuir was shown to describe the adsorption phenomenon better than the Freundlich one. The values of the overall adsorption capacity of methylated biomass suggested that increased biosorbent availability does not necessarily correspond to larger amount of adsorbed metal. FT-IR spectra of dried and methylated biomass of S. platensis allowed us monitoring the efficiency of the methylation process through the analysis of CH and COO- vibrational stretching modes, taken as diagnostic of this process. © 2009 Elsevier B.V. All rights reserved.
Agency: National Aeronautics and Space Administration | Branch: | Program: SBIR | Phase: Phase I | Award Amount: 85.11K | Year: 2012
Genova Engineering proposes to develop and demonstrate a toolset of discrete devices and extraction kits which will leverage existing on-orbit facilities and will permit an expansion of molecular biology capabilities onboard ISS. This toolset, Nucleic Acid And Protein Isolation (NAAPI), is a near-term deployable technology which gives the ISS researcher the ability to isolate DNA, RNA and proteins from precious biological samples. By isolating these target molecules, sample volumes can be reduced by orders of magnitude resulting in reduced downmass. This technology also proposes to adapt a state of the art stabilization technique to enable long-term ambient storage of nucleic acids. This system offers the unique ability to isolate total protein for storage and/or analysis.