Wave-Shaped Round Functions and Primitive Groups

Round functions used as building blocks for iterated block ciphers, both in the case of Substitution-Permutation Networks and Feistel Networks, are often obtained as the composition of different layers which provide confusion and diffusion, and key additions. The bijectivity of any encryption function, crucial in order to make the decryption possible, is guaranteed by the use of invertible layers or by the Feistel structure. In this work a new family of ciphers, called wave ciphers, is introduced. In wave ciphers, round functions feature wave functions, which are vectorial Boolean functions obtained as the composition of non-invertible layers, where the confusion layer enlarges the message which returns to its original size after the diffusion layer is applied. This is motivated by the fact that relaxing the requirement that all the layers are invertible allows to consider more functions which are optimal with regard to non-linearity. In particular it allows to consider injective APN S-boxes. In order to guarantee efficient decryption we propose to use wave functions in Feistel Networks. With regard to security, the immunity from some group-theoretical attacks is investigated. In particular, it is shown how to avoid that the group generated by the round functions acts imprimitively, which represent a serious flaw for the cipher

Crowd-sensing our Smart Cities: a Platform for Noise Monitoring and Acoustic Urban Planning

Environmental pollution and the corresponding control measurements put in place to tackle it play a significant role in determining the actual quality of life in modern cities. Amongst the several pollutant that have to be faced on a daily basis, urban noise represent one of the most widely known for its already ascertained health-related issues. However, no systematic noise management and control activities are performed in the majority of European cities due to a series of limiting factors (e.g., expensive monitoring equipment, few available technician, scarce awareness of the problem in city managers). The recent advances in the Smart City model, which is being progressively adopted in many cities, nowadays offer multiple possibilities to improve the effectiveness in this area. The Mobile Crowd Sensing paradigm allows collecting data streams from smartphone built-in sensors on large geographical scales at no cost and without involving expert data captors, provided that an adequate IT infrastructure has been implemented to manage properly the gathered measurements. In this paper, we present an improved version of a MCS-based platform, named City Soundscape, which allows exploiting any Android-based device as a portable acoustic monitoring station and that offers city managers an effective and straightforward tool for planning Noise Reduction Interventions (NRIs) within their cities. The platform also now offers a new logical microservices architecture

Wave-shaped round functions and primitive groups

Round functions used as building blocks for iterated block ciphers, both in the case of Substitution-Permutation Networks (SPN) and Feistel Networks (FN), are often obtained as the composition of different layers. The bijectivity of any encryption function is guaranteed by the use of invertible layers or by the Feistel structure. In this work a new family of ciphers, called wave ciphers, is introduced. In wave ciphers, round functions feature wave functions, which are vectorial Boolean functions obtained as the composition of non-invertible layers, where the confusion layer enlarges the message which returns to its original size after the diffusion layer is applied. Efficient decryption is guaranteed by the use of wave functions in FNs. It is shown how to avoid that the group generated by the round functions acts imprimitively, a serious flaw for the cipher. The primitivity is a consequence of a more general result, which reduce the problem of proving that a given FN generates a primitive group to proving that an SPN, directly related to the given FN, generates a primitive group. Finally, a concrete instance of real-world size wave cipher is proposed as an example, and its resistance against differential and linear cryptanalyses is also established.acceptedVersio

Trustworthiness of Context-Aware Urban Pollution Data in Mobile Crowd Sensing

Urban pollution is usually monitored via fixed stations that provide detailed and reliable information, thanks to equipment quality and effective measuring protocols, but these sampled data are gathered from very limited areas and through discontinuous monitoring campaigns. Currently, the spread of mobile devices has fostered the development of new approaches, like Mobile Crowd Sensing (MCS), increasing the chances of using smartphones as suitable sensors in the urban monitoring scenario, because it potentially contributes massive ubiquitous data at relatively low cost. However, MCS is useless (or even counter-productive), if contributed data are not trustworthy, due to wrong data-collection procedures by non-expert practitioners. Contextualizing monitored data with those coming from phone-embedded sensors and from time/space proximity can improve data trustworthiness. This work focuses on the development of an algorithm that exploits context awareness to improve the reliability of MCS collected data. It has been validated against some real use cases for noise pollution and promises to improve the trustworthiness of end users generated data

Commissioning and improvements of the instrumentation and launch of the scientific exploitation of OARPAF, the Regional Astronomical Observatory of the Antola Park

The OARPAF telescope is an 80-cm-diameter optical telescope installed in the Antola Mount Regional Reserve, in Northern Italy. We present the results of the characterization of the site, as well as developments and interventions that have been implemented, with the goal of exploiting the facility for scientific and educational purposes. During the characterization of the site, an average background brightness of 22.40mAB (B filter) to 21.14mAB (I) per arcsecond squared, and a 1.5″ to 3.0″ seeing, have been measured. An estimate of the magnitude zero points for photometry is also reported. The material under commissioning includes three CCD detectors for which we provide the linearity range, gain, and dark current; a 31-orders échelle spectrograph with R ∼ 8500 to 15,000 and a dispersion of n = 1.39 × 10 − 6 px − 1λ + 1.45 × 10 − 4 nm / px, where λ is expressed in nm. The scientific and outreach potential of the facility is proven in different science cases, such as exoplanetary transits and active galactic nuclei variability. The determination of time delays of gravitationally lensed quasars, the microlensing phenomenon, and the tracking and the study of asteroids are also discussed as prospective science cases

C-STARS: a collaborative online learning environment for situated translation teaching in higher education

Purpose: Before COVID-19 pandemic, translation students in higher education attended courses on computer-assisted translation to acquire operational knowledge of professional software, without experiencing collaborative/interactive learning. In few European universities skills labs were introduced to offer fieldwork-like activities, but without shared modelling standards and mainly held in presence for few consecutive days. As the COVID-19 pandemic further deprived students of crucial educational experiences, the purpose of this paper is to present an online collaborative learning environment exploiting a customised combination of information and learning applications the students already experienced during the pandemic to smoothen their learning curve and increase the educational effectiveness. Design/methodology/approach: A multi-framework methodology to build and operate a computer-supported online collaborative skills lab for translation students is proposed. Reference standards and guidelines are leveraged to provide participants with a common knowledge ground, to activate the computer-supported collaborative learning perspective, and to ensure an appropriate simulation fidelity. Findings: An end-to-end implementation of the proposed approach along with educational effectiveness analysis performed via complementary assessment strategies is presented. Achieved outcomes highlight significant participation rate, consistent improvement in technical and soft skills at both individual and collective levels, and clear activation of collaborative learning dynamics. Practical implications: Every master degree in translation teaching can adopt this approach by complying with the proposed guidelines. Originality/value: The proposed multi-framework approach is novel and applied to a teaching sector where it is highly needed to fill a pre-existing gap

The Immersive Workbench for Engineering Educators: (Re)Thinking Collaborative and Distance Learning Platforms as Technological Enablers

- Guest Editorial