Search results for "Device"
showing 10 items of 1286 documents
Nuclear Magnetic Resonance for Cultural Heritage
2007
Abstract Nuclear magnetic resonance (NMR) portable devices are now being used for nondestructive in situ analysis of water content, pore space structure and protective treatment performance in porous media in the field of cultural heritage. It is a standard procedure to invert T 1 and T 2 relaxation data of fully water-saturated samples to get “pore size” distributions, but the use of T 2 requires great caution. It is well known that dephasing effects due to water molecule diffusion in a magnetic field gradient can affect transverse relaxation data, even if the smallest experimentally available half echo time τ is used in Carr–Purcell–Meiboom–Gill experiments. When a portable single-sided N…
Media use during adolescence: the recommendations of the Italian Pediatric Society
2019
Abstract Background The use of media device, such as smartphone and tablet, is currently increasing, especially among the youngest. Adolescents spend more and more time with their smartphones consulting social media, mainly Facebook, Instagram and Twitter because. Adolescents often feel the necessity to use a media device as a means to construct a social identity and express themselves. For some children, smartphone ownership starts even sooner as young as 7 yrs, according to internet safety experts. Material and methods We analyzed the evidence on media use and its consequences in adolescence. Results In literature, smartphones and tablets use may negatively influences the psychophysical d…
Smart Assistance for Students and People Living in a Campus
2019
Being part of one of the fastest growing area in Artificial Intelligence (AI), virtual assistants are nowadays part of everyone's life being integrated in almost every smart device. Alexa, Siri, Google Assistant, and Cortana are just few examples of the most famous ones. Beyond these off-the-shelf solutions, different technologies which allow to create custom assistants are available. IBM Watson, for instance, is one of the most widely-adopted question-answering framework both because of its simplicity and accessibility through public APIs. In this work, we present a virtual assistant that exploits the Watson technology to support students and staff of a smart campus at the University of Pa…
Habitual initiation of media use and a response-frequency measure for its examination
2014
When measuring media habits, most scholars rely on retrospective self-reports about behavioral frequency, context stability, or automaticity of the performance. This article develops a new implicit measurement for media research to complement existing approaches, which focuses on measuring the initiation of general, goal-related habits. In the response-frequency measure of media habit (RFMMH), participants are presented with several media use goals and are asked to choose quickly and without deliberation which media device (television set, radio set, newspaper, computer, mobile device) they would use. The more often a media device is chosen, the stronger the mental script to choose this dev…
Does Navigation Always Predict Performance? Effects of Navigation on Digital Reading are Moderated by Comprehension Skills
2016
<p align="left">This study investigated interactive effects of navigation and offline comprehension skill on digital reading performance. As indicators of navigation relevant page selection and irrelevant page selection were considered. In 533 Spanish high school students aged 11-17 positive effects of offline comprehension skill and relevant page selection on digital reading performance were found, while irrelevant page selection had a negative effect. In addition, an interaction between relevant page selection and offline comprehension skill was found. While the effect of relevant page selection was strong in good offline comprehenders, it was significantly reduced in weak offline c…
Assisted labeling for spam account detection on twitter
2019
Online Social Networks (OSNs) have become increasingly popular both because of their ease of use and their availability through almost any smart device. Unfortunately, these characteristics make OSNs also target of users interested in performing malicious activities, such as spreading malware and performing phishing attacks. In this paper we address the problem of spam detection on Twitter providing a novel method to support the creation of large-scale annotated datasets. More specifically, URL inspection and tweet clustering are performed in order to detect some common behaviors of spammers and legitimate users. Finally, the manual annotation effort is further reduced by grouping similar u…
Efficiency of visual time-sharing behavior
2009
In this paper, the effects of two user interface menu structures on a mobile device display, list and grid, are compared in a driving simulation with the measures of visual time-sharing efficiency, visual load, driving performance and secondary task performance. Eighteen participants conducted a set of eight Point-of-Interest (POI) search tasks with the grid- or list-style menus on navigation software during simulated driving. Between-subject analysis revealed that the list-style menu structure supports more efficient and systematic, and thus, safer interaction while driving than the grid-style menu, in terms of time-sharing and total glance time. However, significant effects of the menu st…
Mobile Security with Location-Aware Role-Based Access Control
2012
Published version of an article from the book: Security and privacy in mobile information and communication systems. Also available on SpringerLink: http://dx.doi.org/10.1007/978-3-642-30244-2_15 This paper describes how location-aware Role-Based Access Control (RBAC) can be implemented on top of the Geographically eXtensible Access Control Markup Language (GeoXACML). It furthermore sketches how spatial separation of duty constraints (both static and dynamic) can be implemented using GeoXACML on top of the XACML RBAC profile. The solution uses physical addressing of geographical locations which facilitates easy deployment of authorisation profiles to the mobile device. Location-aware RBAC c…
Improving Password Memorability, While Not Inconveniencing the User
2019
Abstract Passwords are the most frequently used authentication mechanism. However, due to increased password numbers, there has been an increase in insecure password behaviors (e.g., password reuse). Therefore, new and innovative ways are needed to increase password memorability and security. Typically, users are asked to input their passwords once in order to access the system, and twice to verify the password, when they create a new account. But what if users were asked to input their passwords three or four times when they create new accounts? In this study, three groups of participants were asked to verify their passwords once (control group), twice, and three times (two experimental gr…
Improving Perovskite Solar Cells: Insights From a Validated Device Model
2017
To improve the efficiency of existing perovskite solar cells (PSCs), a detailed understanding of the underlying device physics during their operation is essential. Here, a device model has been developed and validated that describes the operation of PSCs and quantitatively explains the role of contacts, the electron and hole transport layers, charge generation, drift and diffusion of charge carriers and recombination. The simulation to the experimental data of vacuum-deposited CH3NH3PbI3 solar cells over multiple thicknesses has been fit and the device behavior under different operating conditions has been studied to delineate the influence of the external bias, charge-carrier mobilities, e…