Search results for "Data type"
showing 10 items of 1183 documents
DEA-like models for efficiency evaluation of specialized and interdependent units
2001
Abstract The problem of evaluating the efficiency of a set of specialized and interdependent decision making subunits (DMSUs) that make up a larger decision making unit (DMU) is considered. The DMSUs are interdependent, in the sense that part of the output produced by each of them may be used as an input by the other ones. They are also specialized, hence non-homogeneous, as they may have not the same inputs and outputs. For this problem, some efficiency indexes are introduced, and they are shown to satisfy some basic properties.
Distributed Coverage of Ego Networks in F2F Online Social Networks
2016
Although most online social networks rely on a centralized infrastructure, several proposals of Distributed Online Social Networks (DOSNs) have been recently presented. Since in DOSNs user profiles are stored on the peers of the users belonging to the network, one of the main challenges comes from guaranteeing the profile availability when the owner of the data is not online. In this paper, we propose a DOSN based on a friend-to-friend P2P overlay where the user's data is stored only on friend peers. Our approach is based on the ego-network concept, which models the social network from the local point of view of a single user. We propose a distributed algorithm which is based on the notion …
Privacy and temporal aware allocation of data in decentralized online social networks
2017
Distributed Online Social Networks (DOSNs) have recently been proposed to grant users more control over the data they share with the other users. Indeed, in contrast to centralized Online Social Networks (such as Facebook), DOSNs are not based on centralized storage services, because the contents shared by the users are stored on the devices of the users themselves. One of the main challenges in a DOSN comes from guaranteeing availability of the users' contents when the data owner disconnects from the network. In this paper, we focus our attention on data availability by proposing a distributed allocation strategy which takes into account both the privacy policies defined on the contents an…
The Use of the Recommended Learning Path in the Personalized Adaptive E-Learning System
2020
This paper promotes the idea of the learning process management in the e-learning system. A personalized adaptive e-learning system is used in this research that comprises three developed topic acquisition sequences: teacher, learner or optimal topic sequences. The learner has the ability to switch between the aforementioned topic sequences. The system stores data about the course acquisition process. The analysis of the stored data demonstrated that a bit more than half of the students used the teacher topic sequence; higher grades in topics got those students who chose the learner or optimal topic sequence; the grades of the half of the students who used the optimal and teacher topic sequ…
From decoding a graph to processing a multimodal message: Interacting with data visualization in the news media
2020
Abstract Data visualisation – in the forms of graphs, charts, and maps – represents a text type growing in prevalence and impact in many cultural domains; education, journalism, business, PR, and more. Research on data visualisation reception is scarce, particularly that related to interactive and dynamic forms of data visualisation in digital media. Taking an approach inspired by grounded theory, in this article I investigate the ways in which young students interact with data visualisations found in digital news media. Combining observations from reading sessions with ten in-depth interviews, I investigate how the informants read, interpreted, and responded emotionally to data visualisati…
Towards semantic-based RSS merging
2009
Merging information can be of key importance in several XML-based applications. For instance, merging the RSS news from different sources and providers can be beneficial for end-users (journalists, economists, etc.) in various scenarios. In this work, we address this issue and mainly explore the relatedness relationships between RSS entities/ elements. To validate our approach, we also provide a set of experimental tests showing satisfactory results. © 2009 Springer-Verlag Berlin Heidelberg
Aggregation in Input–Output Tables: How to Select the Best Cluster Linkage
1991
In this paper we try to give a solution to the aggregation problem on working with Input–Output tables. First of all we verify the degree of similarity among the production functions of the industries which aggregate in each sector. Secondly, once we have established the aggregation by using different cluster analysis, we set a number of conditions required to choose the proper linkage method that allows us to characterize the process of aggregation (weighted or unweighted) of the input–output table.
Input-output feedback linearizing control of linear induction motor taking into consideration the end-effects. Part I: Theoretical analysis
2015
Abstract This first part of a paper, divided into two parts, deals with the theoretical formulation of the input–output feedback linearization (FL) control technique as to be applied to linear induction motors (LIMs). Linear induction motors, differently from rotating induction motors (RIMs), present other strong non-linearities caused by the so-called dynamic end effects, leading to a space-vector model with time-varying inductance and resistance terms and an additional braking force term. This paper, starting from a dynamic model of the LIM taking into consideration its dynamic end effects, previously developed by the same authors, defines a feedback linearization (FL) technique suited fo…
Input-Output Feedback Linearizing Control of Linear Induction Motor Taking into Consideration the End-Effects. Part II: Simulation and Experimental R…
2015
This is the second part of a paper, divided in two parts, dealing with the application of the input–output feedback linearization (FL) control technique to linear induction motors (LIMs). The first part has treated the theoretical formulation of the input–output feedback linearization control technique as to be applied to linear induction motors. This second part describes the set of tests, both in numerical simulations and experiments, performed to assess the validity of the control technique. In particular, it addresses the issues of the sensitivity of the FL control versus the LIM electrical parameters’ variations and the improvements achievable by considering the LIM dynamic end effects…
Input-Output Finite-Time Stability of Discrete-Time Impulsive Switched Linear Systems with State Delays
2013
Published version of an article in the journal: Circuits, Systems, and Signal Processing. Also available from the publisher at: http://dx.doi.org/10.1007/s00034-013-9610-7 This paper is concerned with the problem of input-output finite-time stability (IO-FTS) for discrete impulsive switched systems with state delays. Sufficient conditions are presented for the existence of IO-FTS for such systems under the cases of certain switching, arbitrary switching, and uncertain switching. All the obtained results are formulated in a set of linear matrix inequalities (LMIs). Two numerical examples are given to illustrate the effectiveness of the proposed results.