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Abstract This paper presents experimental and numerical investigation of mistuned forced responses of an integrally bladed disk with full set of underplatform dampers (UPDs). This research aims at providing: 1. An experimental benchmark for nonlinear dynamics of a mistuned bladed disks with UPDs. 2. A numerical model that can account for features of a mistuned forced response level. Accordingly, a detailed experimental campaign is conducted on a static test rig called Octopus. This rig is specifically designed to investigate the dynamics of a full-scale integrally bladed disk (blisk) with UPDs in a noncontact manner so that the dynamic response of the system is not modified. The effect of mistuning on experimental forced response levels is assessed and a linearized model is proposed to predict the modulation of frequency response functions (FRFs) due to the frequency splitting. In the development of the model, the mistuning pattern identified from the linear blisk without UPDs is used and it is assumed that adding the dampers does not change the structural mistuning of the blisk. In this study, the fundamental mistuning model identification (FMM ID) was employed to identify the mistuning pattern of the blisk. It is shown that the proposed model successfully predicts the modulation of linear mistuned FRFs. The linearized model is also able to predict the modulation of nonlinear mistuned FRFs in stick condition (when nonlinear friction damping is negligible) with a good accuracy validating this assumption that adding the dampers does not change the mistuning pattern.

In recent years, the occurrence and damages of the blackouts in power systems saw an increase. Many of them are due to the impacts of climate change. However, tracing all blackouts that happened in the world and associating them with specific causes is quite challenging due to the huge amount of information over the Internet. In this paper, we proposed a framework for automatically analyzing the information collected from Internet based on the Ontological Approach coupled with Artificial Intelligence (AI) tailored for Natural Language Processing, which permits information extraction from reports to better understand the major entities of a power outage, their role, and the connections among them. However, our test shows that, despite the promising results of Named Entity Recognition in other fields, the lack of a standard ontology for blackout analysis is both the proof and the cause for the missed chance of exploiting this AI branch.

Abstract Even under the powerful thrust of 20–20–20 measures, solar thermal systems are experiencing a slow-down in their development in most EU countries. One reason is their traditional confinement to sanitary hot water (SHW) production; another one is the growing competition with photovoltaic (PV) systems. In order to widen the use of solar thermal collectors, they should also be able to contribute to space heating and cooling and become Multi-Purpose Solar Thermal Systems (MPSTS). This paper addresses the issue of optimal sizing of MPSTS. The criterion adopted is based on maximization of Net Present Value and has been applied to some cities in Italy and in Pakistan with diverse climate conditions. Results show that optimal thermal collector areas per peak cooling demand ( A c / P c ) can be conveniently expressed as a function of Peak Heating to Cooling Ratio ( P h / P c ). Optimum A c / P c varies between 3 and 5 m 2 /kW c and decreases with increasing P h / P c . The paper also analyses and compares a MPSTS with a multi-purpose PV-based heat pump system using a traditional one (boiler and compression chiller) as reference. Results show that steadily decreasing prices have made PV systems more favorable, even without consideration of public subsidies.

The present paper is focused on the design, optimization and analysis of a complex parallel hybrid electric vehicle, equipped with two electric machines on both the front and rear axles, and on the evaluation of its potential to reduce fuel consumption and NOx emissions over several driving missions. The vehicle has been compared with two conventional parallel hybrid vehicles, equipped with a single electric machine on the front axle or on the rear axle, as well as with a conventional vehicle. All the vehicles have been equipped with compression ignition engines. The optimal layout of each vehicle was identified on the basis of the minimization of the overall powertrain costs during the whole vehicle life. These costs include the initial investment due to the production of the components as well as the operating costs related to fuel consumption and to battery depletion. Identification of the optimal powertrain control strategy, in terms of the management of the power flows of the engine and electric machines, and of gear selection, is necessary in order to be able to fully exploit the potential of the hybrid architecture. To this end, two global optimizers, one of a deterministic nature and another of a stochastic type, and two real-time optimizers have been developed, applied and compared. A new mathematical technique has been developed and applied to the vehicle simulation model in order to decrease the computational time of the optimizers. First, the vehicle model equations were written in order to allow a coarse time grid to be used, then, the control variables (i.e., power flow and gear number) were discretized, and the values of the main model variables were evaluated and stored in a matrix (referred to as configuration matrix), for all the possible combinations of control variables and for each time node, before the optimization process. In this way, the optimizers can read the actual values of the relevant variables from the pre-processed data, instead of calculating them iteratively during the optimization stage. The performance of the hybrid vehicles has been evaluated over several driving missions, including the NEDC, the FTP, the AUDC, the ARDR and the AMDC, and a detailed energetic analysis has been carried out in order to clearly identify the key operating modes that contribute most to the fuel consumption and NOx emission savings of the different hybrid architectures.

From marketing to logistics, from the sourcing of raw materials to the production of always new products and services, from better warehouse management to the possibility of creating widespread networks of suppliers and customers, according to Henrik Von Scheel ‘Big data are disrupting every aspect of the business’. In the fashion sector, this approach ranges from the exploration of future scenarios to the qualification of the entire system through the harmonisation of all activities tending towards transparency and greater awareness. This contribution is proposed through the critical lens of design as an original catalyst for change, as a tool for methodological, technical and creative reading for socio-territorial and productive transformations, with the aim of providing a general overview of the contemporary state of the art about the use of big data in the fashion industry.

Purpose – Two main activities of the EC FP7 Risk of Energy Availability: Common Corridors for Europe Supply Security (REACCESS) project applied a systematic approach to collect the main characteristics of energy supply corridors starting from mining activities in exporting regions up to the import infrastructures and capacities of EU27+countries. The aim of the present paper is to summarise identified information on import potentials and the possible corridors for the EU27+energy supply of the future. This information is used as new starting point for the energy system modelling in the REACCESS project.Design/methodology/approach – Detailed information on existing, planned or potential developments derived from literature reviews and expert surveys, as well as from our own calculations, was compiled in a consistent database. By using suitable geographic information system (GIS) tools, all the identified energy supply routes were represented graphically and analysed with reference to their spatial characte...

AbstractDas Verhalten (Codeposition) der Verunreinigungen mit Ni, Co, Cu, Cd, Sb, Ge, As oder Bi bei der Zn‐Abscheidung aus H,SO4‐Bädern (O. l ‐1.0 N) wurde durch chemische Analyse, Stromwirkungsgrad und SEM der Kathodenoberfläche untersucht, auch bei Zusatz von Gummi arabicum zum Elektrolyten.

During 2010-2013, Baltic Countries (Estonia, Latvia, Lithuania), deregulated their power markets and joined the Nord-Pool market. Today, major share of electricity in Baltic countries is produced from fossil fuels. Over the past years, the increasing penetration of renewable energy systems intensified in order to meet the European targets. In particular, installing wind power dramatically rises as a result of a great potential in Northern Europe. This paper attempts to provide an overview of the possible impacts of growing wind power on market power potential in Baltic countries’ electricity market. The Herfindahl-Hirschman Index (HHI), which is a common measure of market concentration, is chosen to conduct this exploratory study. HHI index trend in Baltic over the years is evaluated and compared with the rise of wind power. The results show how Baltic area is a highly concentrated marketplace, but wind power is partly changing this.

Abstract A theoretical model of a regenerative blower used for the hydrogen recirculation of a Proton Exchange Membrane (PEM) fuel cell (FC) for automotive applications has been implemented and validated by means of experimental data. A momentum exchange theory was used to determine the head-flow rate curves, whereas the circulatory flow rate was determined through a theory based on the consideration of the centrifugal force field in the side channel and in the impeller vane grooves. The model allows a good forecast to be made of the blower behaviour, and only needs its main geometrical characteristics and some fluid-dynamic data as input. For this reason, the model could be very interesting, especially during the first sizing and the design activity of the blower.