1,721,151 research outputs found
Robustified distributed model predictive control for coherence and energy efficiency-aware platooning
No full textPlatooning has become one of the most appealing formations for intelligent vehicles safety enhancement and traffic regulation. Besides the traditional control algorithms, which are required to enforce at least local and string stability, more complex control schemes can be designed to cope with advanced requirements. In this paper, a suitable Distributed Model Predictive Control (DMPC) scheme, robustified with a second -order Integral Sliding Mode (ISM) correction term, is proposed to enforce and maintain coherence during cruising, while considering energy efficiency during acceleration/deceler-ation phases. While the former aspect has a complex impact on traffic regulation, especially when a large number of vehicles is considered, the latter is of primary importance in an increasingly eco-friendly transportation systems design. The proposed approach is well suited for real-world implementation, and can constitute a valid basis for more advanced control architectures. Simulation results highlight the effectiveness of the proposed architecture in maintaining the formation while guaranteeing a robust achievement of the required performance
Application of the Network Psychometric Framework to Measurement Burst Designs
No full textNetwork Psychometrics emerged in the last years as an approach that allows investigating how different elements of a system interact and how these interactions change across occasions. The present work aims to show the potentialities of the Network Psychometric framework to examine the stability of dynamics of change of psychological processes. Specifically, we tested the applicability of the recently introduced psychonetrics toolbox to (a) model within-subjects (both contemporaneous and temporal) and between-subject (stable individual differences) dynamics with data collected with a measurement burst design (MBD, two 14-day bursts); and (b) examine the temporal stability (or instability) of the process’ dynamics by directly comparing the two bursts in terms of both within and between parameters’ invariance. The illustrative example was about the process of meaning-making, whose dynamics of change were examined across two different contextual conditions during the COVID-19 pandemic. A step-by-step procedure to apply psychonetrics to MBDs is provided in an Open Science Framework project
Integral Second-Order Sliding Modes for Robust Prescribed-Time Leader-Follower Consensus Control with Partial Information
No full textIn this paper, the possibility of generating second order integral sliding modes for the robust finite-time solution of leader-follower consensus problems in cooperative multi-agent systems (MAS) is presented. A novel approach is discussed for agents with first or second order dynamics, able to enforce convergence exploiting only partial information (i.e. the relative distance between the first state of each agent and those of its neighbours) under the assumption that the network graph contains a directed spanning tree. The adoption of integral sliding manifolds allows for the elimination of the reaching phase, which in turn guarantees robustness from the initial time instant, and consensus reaching in prescribed time. Chattering alleviation is discussed in order to obtain a continuous control. The proposal is analysed both in theory and simulation, where the obtained results highlight the validity of the strategy
Constrained Sliding-Mode Control: A Survey
No full textIn this chapter, the robust control of input and state-constrained nonlinear systems is discussed from the perspective of sliding-mode control. The proposals currently available in the literature are summarized and some of them are briefly discussed, in particular cases providing also commented examples
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
