Can videos affect learning outcomes? Evidence from an actual learning environment

Educational technology research and development - We examine the effect of an innovation in an educational context, a class of 500?+?first-year economics students at a well-known...     

Multispectral data cube acquisition of aligned images for document analysis by means of a filter-wheel camera provided with focus control

Multispectral imaging techniques are widely used to analyse and restore digital images of ancient documents degraded over time. In particular, acquisitions in infrared and ultraviolet bands can reveal information invisible by naked eye, which is not captured by conventional RGB imaging. Multispectral acquisitions are usually performed with filter-wheel cameras that mount a series of interference filters in front of the sensor to select the spectral band in which the document has to be acquired. Due to the use of different filters, the focus of the lens changes and it is necessary to adjust it manually for each filter, because such imaging systems are devoid of automatic focusing. Thus the acquired images may not be perfectly in-focus and have misalignments. In this work we present an automatic solution to acquire a multispectral data cube of aligned images that can be used in document analysis to extract and/or separate information through enhancement techniques. A custom-made motorized autofocus system controlled by software has been installed on a filter-wheel camera, which allows us to acquire in-focus images automatically at each filter changing, and a registration method based on Fourier-Mellin transform aligns these images. A preliminary calibration is performed to set the focusing of each filter with the working distance. As a result, the camera can capture images independently from the contrast of the scene, also in presence of documents with homogeneous texture. The proposed solution reduces considerably the acquisition time and offers a tool to acquire automatically the data cube to be used in further image analysis techniques. The results of experimentations are hereby presented and discussed.     

Building stone and related weathering in the architecture of the ancient city of Naples

The survey of materials constituting the buildings of the ancient city centre of Naples and of their decay typologies was carried out. Reports were entered in a database which enabled us to draw two thematic maps in a digital format: one of materials and lithotypes, and one showing weathering. On this basis, quantitative evaluations of the lithotypes were carried out. The research pointed out that the use of different lithotypes was mainly as a result of their availability and/or ease of exploitation. Furthermore, the importance of the preservation of the quarrying sites was stressed, both for their historical and cultural interest and, above all, for possible forthcoming provisioning finalized to restorations. The analysis of the results, made on a geo-mineralogical basis, as well as the thematic maps, gives a basic tool which will be very useful to those professionals involved in preservation of cultural heritage.     

Further clarifications about the success-index

The aim of this brief communication is to reply to a letter by Kosmulski (Journal of Informetrics 6(3):368–369, 2012), which criticizes a recent indicator called “success-index”. The most interesting features of this indicator, presented in Franceschini et al. (Scientometrics, in press), are: (i) allowing the selection of an “elite” subset from a set of publications and (ii) implementing the field-normalization at the level of an individual publication. We show that the Kosmulski's criticism is unfair and inappropriate, as it is the result of a misinterpretation of the indicator.     

Hermite neural network-based second-order sliding-mode control of synchronous reluctance motor drive systems

This paper proposes a novel Hermite neural network-based second-order sliding-mode (HNN-SOSM) control strategy for the synchronous reluctance motor (SynRM) drive system. The proposed HNN-SOSM control strategy is a nonlinear vector control strategy consisting of the speed control loop and the current control loop. The speed control loop adopts a composite speed controller, which is composed of three components: 1) a standard super-twisting algorithm-based SOSM (STA-SOSM) controller for achieving the rotor angular speed tracking control, 2) a HNN-based disturbance estimator (HNN-DE) for compensating the lumped disturbance, which is composed of external disturbances and parametric uncertainties, and 3) an error compensator for compensating the approximation error of the HNN-DE. The learning laws for the HNN-DE and the error compensator are derived by the Lyapunov synthesis approach. In the current control loop, considering the magnetic saturation effect, two composite current controllers, each of which comprises two standard STA-SOSM controllers, are designed to make direct and quadrature axes stator current components in the rotor reference frame track their references, respectively. Comparative hardware-in-the-loop (HIL) tests between the proposed HNN-SOSM control strategy and the conventional STA-SOSM control strategy for the SynRM drive system are performed. The results of the HIL tests validate the feasibility and the superiority of the proposed HNN-SOSM control strategy.     

The Supply of Arts Labour : Towards a Dynamic Approach

Earlier work on the supply of labour of artists has shown that, whenever workers derive satisfaction from the process of work, which is usually the case for artists, some traditional results are reversed. As their proponents make clear this analysis is essentially static, as it does not take into account the intertemporal dimension of the supply of labour. The paper argues that to provide such a dynamic analysis three routes are available: the human capital approach, the household production approach and the evolutionary approach. The paper, therefore, is aimed at discussing the adequacy of various theoretical approaches to the treatment of a specific question.     

Organisational Change and the Institutionalisation of University Patenting Activity in Italy

As universities are increasingly called by their national governments for a more entrepreneurial management of public research results, they started to develop internal structures and policies to take a proactive role in the commercialisation of university research. For the first time, this paper presents a detailed chronicle of how country-level reforms on Intellectual Property Rights (IPRs) were translated into organisation-level mechanisms to regulate university-patenting activity. The analysis is based on the complete list of patent policies issued between 1993 and 2009 by the population of Italian universities. Our evidence suggests that universities first dealt with legislative changes on IPRs by enacting isomorphic behaviours, then by creating a community of practices, and finally by leveraging on such community to influence government reforms on IP-related matters. We discuss our results in the light of institutional theory and public policy.