Search results for " device"
showing 10 items of 1082 documents
Computing methods for resilience: evaluating new building components in the frame of SECAPs
2019
Resilience represents a new important feature that the anthropic systems, and cities among them, are called to cope with. In fact, the increasing negative stresses to which urban contexts are exposed, and mainly the climatic pressures, call for the capability of adapting to these modifications and, possibly, to restore the ex-ante situations. The role of the buildings and their envelope components is of crucial importance to this aim. This paper analyses the features of resilience of the roofs of buildings by means of proper quantitative indexes. On purpose, the performances of green and cool roofs are compared. The possibility of adopting nonstructural solutions, like the windows shading d…
The security of mobile business applications based on mCRM
2020
A development of mobile technologies, and their common use in business, creates new challenges for people dealing with data security in the organization. This paper explores the types and nature of threats to the enterprise that result from the widespread use of business applications on smartphones (e.g. mobile CRM). The analysis has been focused on smartphones and tablets running on the Android operating system. We used STRIDE - a threat modeling technique commonly used to detect vulnerabilities in software security. We propose its modification to better design and implement solutions for the security of mobile devices. We also used the Data Flow Diagram and the Attack Tree concept to anal…
Graphene as a tunable resistor
2014
We present the design of a graphene-based electronically tuneable microstrip attenuator operating at a frequency of 5 GHz. The use of graphene as a variable resistor is discussed and the modelling of its electromagnetic properties at microwave frequencies is fully addressed. The design of the graphene-based attenuator is described. The structure integrates a patch of graphene, whose characteristics can range from being a fairly good conductor to a highly lossy material, depending on the applied voltage. By applying the proper voltage through two high-impedance bias lines, the surface resistivity of graphene can be modified, thereby changing the insertion loss of the microstrip attenuator.
Fingerprint Quality Evaluation in a Novel Embedded Authentication System for Mobile Users
2015
The way people access resources, data and services, is radically changing using modern mobile technologies. In this scenario, biometry is a good solution for security issues even if its performance is influenced by the acquired data quality. In this paper, a novel embedded automatic fingerprint authentication system (AFAS) for mobile users is described. The goal of the proposed system is to improve the performance of a standard embedded AFAS in order to enable its employment in mobile devices architectures. The system is focused on the quality evaluation of the raw acquired fingerprint, identifying areas of poor quality. Using this approach, no image enhancement process is needed after the …
A Multi-Expert Based Approach to Continuous Authentication of Mobile-Device Users
2003
Currently used in mobile devices PIN-based user authentication cannot provide a sufficient security level. Methods based on multi-modal user authentication involving biometrics (i.e. physical and behavioral characteristics of a person) may be employed to cope with this problem. However, dealing with physical characteristics only, these methods are either unable to provide continuous and user-friendly identity verification, or are resource consuming.
Sguardo autobiografico e dispositivi iconotestuali in Michele Mari
2020
Oggetto del contributo è la questione dell’autorialità in tre composizioni iconotestuali e autobiografiche di Michele Mari: Filologia dell’anfibio. Diario militare (1995), Asterusher. Autobiografia per feticci (2015) e Leggenda privata (2017). Nel diario, Filologia dell’anfibio, Mari racconta nella forma di uno pseudo-trattato il periodo trascorso presso il Centro Addestramento Reclute di Como. Il testo è illustrato da disegni tratti dai propri diari dell’epoca. In Asterusher. Autobiografia per feticci, ricalcando la forma tripartita dell’emblematica, Mari ha giustapposto le fotografie di oggetti familiari e alcune citazioni tratte dalle sue opere precedenti. Leggenda privata è un’autoficti…
Batteries for Aerospace: A Brief Review
2018
This paper presents a brief overview on batteries for aerospace application. In particular, More Electric Aircraft (MEA) and All Electric Aircraft (AEA) concepts are introduced at first, together with their main advantages and drawbacks. Subsequently, opportunities and issues related to the employment of batteries on aircrafts are presented and briefly discussed. Reference is then made to aircraft power system architectures and battery technologies, as well as on the state-of-the-art of battery management systems, state-of-charge and state-of-health estimations, and thermal management.
On-board Energy Consumption Assessment for Symbolic Execution Models on Embedded Devices
2020
Internet of Things (IoT) applications operate in several domains while requiring seamless integration among heterogeneous objects. Regardless of the specific platform and context, IoT applications demand high energy efficiency. Adopting resource-constrained embedded devices for IoT applications means ensuring low power consumption, low maintenance costs and possibly longer battery life. Meeting these requirements is particularly arduous as programmers are not able to monitor the energy consumption of their own software during development or when applications are finally deployed. In this paper, we discuss on-board real-time energy evaluation of both hardware and software during the developm…
Wireless battery chargers for portable applications: Design and test of a high-efficiency power receiver
2013
In this study, the authors present a 5 W wireless battery charger for handheld devices. Efficiency-related issues are addressed. A power receiver architecture which improves power conversion efficiency is proposed. Design hints are provided for further applications. Comparison with a conventional architecture is provided as well. Laboratory prototypes of both the proposed and the conventional architectures have been realised. Both prototypes are tested by using the same power transmitter to perform a valuable comparison. As shown by the experimental results, in the receiver side power conversion efficiency is increased up to 99% thanks to the proposed solution.
<title>Functional models of electrochromic devices: cycling capacity and degradation</title>
1997
Electrical transfer and diffusion of ions and the irreversibility of ion and electron processes in heterojunctions are responsible for degradation of ionic devices. These processes for electrochromic devices (ECD) determine the cycling capacity and lifetime. The basic problem here is how to match the electrochemical parameters (including chemical potential) of heterojunction. The experiments had been carried out on ECD based on system: (phi) - -(phi) , where AAH is solid electrolyte based on antimony acid hydrates. The cycling capacity and degradation processes of ECD are investigated by electro-optical and electro-chemical spectroscopy. The analysis of experimental data are based on assump…