Search results for "Ratings"
showing 10 items of 79 documents
Design of a narrow-band filter based on the Brewster phenomenon for microwave applications
2017
A high-efficiency narrow-band filter based on a Dielectric Frequency-Selective Surface (DFSS) has been predicted theoretically for oblique plane-wave incidence. A DFSS showing total reflection at a frequency of 10.5 GHz, based on the Brewster phenomenon for TM polarization, has been designed with a single dielectric grating, showing extremely low-reflectance sidebands adjacent to the resonance peak. The angular and spectral response of the designed filter has been studied. In addition, dielectric ohmic losses have been accounted for in this structure. This work was supported by the Agencia Estatal de Investigación (AEI) and by the Unión Europea through the Fondo Europeo de Desarrollo Region…
Monitoring System of Passive Optical Networks with Remotely Power Supply of Optical Network Terminals
2011
In this paper, the authors, present last results on a low cost method to monitoring Passive-Optical-Network, which it uses Fiber-Bragg-Gratings and a modified Optical-Time-Domain-Reflectometer, and a remote power supply of Optical-Network-Terminals by a bivalent-use cable.
Periodic time-domain modulation for the electrically tunable control of optical pulse train envelope and repetition rate multiplication
2012
An electrically tunable system for the control of optical pulse sequences is proposed and demonstrated. It is based on the use of an electrooptic modulator for periodic phase modulation followed by a dispersive device to obtain the temporal Talbot effect. The proposed configuration allows for repetition rate multiplication with different multiplication factors and with the simultaneous control of the pulse train envelope by simply changing the electrical signal driving the modulator. Simulated and experimental results for an input optical pulse train of 10 GHz are shown for different multiplication factors and envelope shapes. © 2006 IEEE.
Assessment of students' situation-specific classroom engagement by an InSitu Instrument
2016
The present study aims to expand the current understanding of engagement by examining variations in students' situation-specific engagement in lower secondary school. In addition, the validity and reliability of a new situation-specific InSitu Instrument were examined. The sample consisted of 1809 Finnish students attending Grade 7. The students filled in mobile ratings on their lesson-specific engagement after lessons. Furthermore, they answered questionnaires concerning their overall engagement, achievement beliefs, and task values in math and literacy. The results showed substantial variation within and between students in situational engagement. A five-factor structure was identified fo…
Honeypot Utilization for Network Intrusion Detection
2018
For research purposes, a honeypot is a system that enables observing attacker’s actions in different phases of a cyberattack. In this study, a honeypot called Kippo was used to identify attack behavior in Finland. The gathered data consisted of dictionary attack login attempts, attacker location, and actions after successful login. From the data, attacker behavior was analyzed. Differentiating bots from human actors, linking scanning activity to further attack steps, and identifying malware and tracking malware sites were all done. The knowledge gained could be used to enhance an organization’s cyber resiliency by identifying attacker motivations and the tools used. Automating analysis of h…
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…
Modern Blue Pills and Red Pills
2020
This article presents the concept of blue pill, a stealth hypervisor-based rootkit, that was introduced by Joanna Rutkowska in 2006. The blue pill is a malicious thin hypervisor-based rootkit that takes control of the victim machine. Furthermore, as the blue pill does not run under the operating system context, the blue pill is very difficult to detect easily. The red pill is the competing concept (i.e., a forensics software that runs on the inspected machine and detects the existence of malicious hypervisor or blue pill). The concept of attestation of a host ensuring that no hypervisor is running was first introduced by Kennel and Jamieson in 2002. Modern advances in hypervisor technology …
“Facebocrastination”? Predictors of using Facebook for procrastination and its effects on students’ well-being
2016
Procrastinating with popular online media such as Facebook has been suggested to impair users well-being, particularly among students. Building on recent procrastination, self-control, and communication literature, we conducted two studies (total N=699) that examined the predictors of procrastination with Facebook as well as its effects on students academic and overall well-being. Results from both studies consistently indicate that low trait self-control, habitual Facebook checking, and high enjoyment of Facebook use predict almost 40 percent of the variance of using Facebook for procrastination. Moreover, results from Study 2 underline that using Facebook for the irrational delay of impor…
Too many passwords? How understanding our memory can increase password memorability
2018
Abstract Passwords are the most common authentication mechanism, that are only increasing with time. Previous research suggests that users cannot remember multiple passwords. Therefore, users adopt insecure password practices, such as password reuse in response to their perceived memory limitations. The critical question not currently examined is whether users’ memory capabilities for password recall are actually related to having a poor memory. This issue is imperative: if insecure password practices result from having a poor memory, then future password research and practice should focus on increasing the memorability of passwords. If, on the other hand, the problem is not solely related …
Bargaining with partially revocable commitments: a simple model
2002
Fershtman and Seidmann (1993) showed that the presence of an irrevocable endogenous commitment with a fixed deadline results in the so called deadline effect. We examine the robustness of this result to the presence of a much more general class of commitments: partially revocable commitments.