3,369 research outputs found
Multiscale probabilistic evaluation of the footbridge crowding. Part 2: Crossing Pedestrian position
Full text link\u3cp\u3eIn the previous Part of this study, an attempt to estimate the c.o.v. of the pedestrian density approaching a footbridge has been made. In analogy to wind engineering, where statistics on the incoming wind are complemented with the description of the flow around the obstacle to provide the aerodynamic forces on the structure, the obtained result is not conclusive. In pedestrian dynamics, the density along the footbridge cannot be confused with the incoming one if the pedestrian dynamics is affected by the walkway features (side barriers, walkway geometry, obstacles). On the other hand, differently from fluid dynamics, pedestrian motion is a multiscale phenomenon, which can be described both at the macroscopic scale (continuous medium) and at the microscopic scale (granular medium). The pedestrian density described in Part I can be ascribed to the former. Conversely, the uncertain location (in space and time) of each pedestrian at the entrance of the footbridge must be sampled and treated at the microscopic scale. Such uncertainty on positions further propagates spanwise along the walkway, being transported by pedestrians themselves. Evidences of this are available in literature based either on in-situ observations or on lab experiments. In this part of the study, the span-wise propagation of the uncertainty generated by the incoming pedestrian density is studied in the framework of the Monte Carlo method. In particular, a statistical analysis of repeated microscopic simulations of a first order crowd model accounting for body size is performed. Inlet conditions are prescribed on the basis of the statistics of the crowd density (described in part I), by assigning probability laws to the pedestrian chord-wise inlet positions and to the inter-arrival times. The final goal of the model is to estimate the propagation of the incoming variability along the footbridge. The application of the model to an ideal footbridge is provided.\u3c/p\u3
RSSi-based visitor tracking in museums via cascaded AI classifiers and coloured graph representations
Full text linkIndividual tracking of museum visitors based on portable radio beacons, an asset for behavioural analyses and comfort/performance improvements, is seeing increasing diffusion. Conceptually, this approach enables room-level localisation based on a network of small antennas (thus, without invasive modification of the existent structures). The antennas measure the intensity (RSSi) of self-advertising signals broadcasted by beacons individually assigned to the visitors. The signal intensity provides a proxy for the distance to the antennas and thus indicative positioning. However, RSSi signals are well-known to be noisy, even in ideal conditions (high antenna density, absence of obstacles, absence of crowd, ...). In this contribution, we present a method to perform accurate RSSi-based visitor tracking when the density of antennas is relatively low, e.g. due to technical constraints imposed by historic buildings. We combine an ensemble of "simple" localisers, trained based on ground-truth, with an encoding of the museum topology in terms of a total-coloured graph. This turns the localisation problem into a cascade process, from large to small scales, in space and in time. Our use case is visitors tracking in Galleria Borghese, Rome (Italy), for which our method manages >96% localisation accuracy, significantly improving on our previous work (J. Comput. Sci. 101357, 2021)
Modeling Routing Choices in Unidirectional Pedestrian Flows
Full text linkIn this work we present a simple routing model capable of capturing pedestrians path choices in the presence of a herding effect. The model is tested and validated against data from a large scale tracking campaign which we have conducted during the GLOW 2019 festival. The choice between alternative paths is modeled as an individual cost minimization procedure, with the cost function being associated to the (estimated) traveling time. In order to trigger herding effects the cost function is supplemented with a penalty term, modulated as a function of the fraction of pedestrians walking along each route. The model is shown to provide an accurate quantitative description of the decision process
Top Management Teams in family controlled companies: ‘Familiness’, ‘faultlines’ and the impact on financial performance
No full textResearch on Top Management Teams (TMTs) in family controlled companies has been relatively scant so far. We extended the upper echelon perspective into the family business research in order to understand whether and how ‘familiness’ can provide further insights besides the classical TMTs’ demographics in explaining variations in firms’ financial performance. Moreover, we assess whether or not ‘familiness’ is always beneficial to firm performance, and to what extent. We tested our hypotheses on 93 TMTs out of a sample of 500 largest Italian family controlled companies by turnover we used for a questionnaire survey. We developed family firms-specific measures of TMTs’ ‘familiness’. Results indicated that while the presence of a family CEO was found to be beneficial for firm performance, the coexistence of ‘factions’ of family and nonfamily managers within the TMT had the potential to determine schisms among the subgroups and consequently to hurt firm performance. The support we found for the hypothesized U-shaped relationship between the ratio of family members in the TMT and firm performance represented a novel application of the ‘faultlines’ concept
Osservatorio AUB (AIdAF-Unicredit-Bocconi) su tutte le aziende familiari di medie e grandi dimensioni
No full textNo abstract availabl
Family firms configurations and finacial performance: is family leadership always beneficial
No full textNo abstract availabl
ll Governo delle Imprese Italiane Quotate a Controllo Familiare: i Risultati di una Ricerca Esplorativa
No full textQuesto lavoro mira a dare indicazioni sul governo
delle imprese familiari quotate alla Borsa Italiana
combinando il tradizionale approccio di ricerca
su caratteristiche e funzionamento del CdA nelle grandi
imprese ad azionariato diffuso con le specificità delle imprese a controllo familiare. L’ipotesi è che, nonostante un diffuso scetticismo sull’efficacia dell’azione di governo dei CdA, soprattutto in imprese a controllo familiare, essi possano fornire contributi critici spesso sottovalutati. Il CdA non è solo l’organo che deve, o dovrebbe, controllare il management. Ricerca e pratica a livello internazionale convergono nell’attribuire al CdA almeno due ruoli principali, di controllo e di servizio, i quali, e in particolare quello di servizio, diventano tanto più critici nelle imprese familiari. In esse, infatti, il CdA può fornire contributi aggiuntivi integrando eventuali gap di competenze dei familiari attraverso l’inserimento di consiglieri esterni selezionati in base al loro background professionale. Il problema sembra essere proprio quello della scelta del corretto mix di consiglieri familiari e non, nonché dei profili manageriali più adatti a operare nel contesto comunque specifico delle imprese controllate da una famiglia. La selezione di consiglieri e manager, che sia svolta da agenzie esterne o dal comitato nomine, rappresenta in altri termini la futura sfida di buon governo delle imprese a controllo familiare
A imagem de Alessandro Baricco no Brasil
Full text linkDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão, Programa de Pós-Graduação em Estudos da Tradução, Florianópolis, 2013.Com a intenção de delinear o modo pelo qual o escritor italiano Alessandro Baricco se inseriu no sistema literário brasileiro e os caminhos percorridos pelos seus livros traduzidos, esta dissertação dá voz às experiências tradutórias de seus tradutores. A inserção de Bariccono Brasil tem seu início em 1997, através de uma proposição da Profa. Dra. Roberta Barni à editora Iluminuras da tradução de Oceano Mare. A partir daí, outras sete obras foram publicadas no Brasil, sendo três delas traduzidas por Roberta Barni e as outras quatro por quatro tradutores diferentes. De um lado, considera-se o tradutor como figura principal namediação entre culturas, e, de outro, se analisa a realidade desta figuradentro do sistema literário, sua invisibilidade, seus limites e o exercíciode sua profissão. A pesquisa conta, ainda, com críticas e resenhas referentes ao autor italiano publicadas em jornais consagrados no Brasil, considerando estas como parte constituinte da imagem de Baricco refletida em território nacional. Abstract : Intending to delineate the way the Italian writer Alessandro Baricco has been inserted in the Brazilian literary system and the paths his translated books have followed, this thesis gives voice to the translating experiences of his translators. Baricco's insertion in Brazil began in 1997, through a personal project of Dr. Roberta Barni, with her translation of Oceano Mare. Since then, seven other of his works have been published in Brazil, three of which were translated by Roberta Barni and the other four by four different translators. On the one hand,the translator is considered as the main figure in mediation betweencultures and, on the other, this figure's reality is analyzed within theliterary system: its invisibility, its limits and its professional practice. Criticisms and reviews of this Italian author published in well established Brazilian newspapers are also considered, with the understanding that they are part of Baricco's image reflected here
Uncertainties in crowd dynamic loading of footbridges: A novel multi-scale model of pedestrian traffic
No full textThe study of the probabilistic response of pedestrian-excited structures as well as their reliability analysis need to take into account the influence of a large number of uncertain parameters ascribed to structural characteristics, single pedestrian walking features and pedestrian traffic phenomena. Although pedestrian traffic is characterized by an intrinsic high variability and plays a key role in determining the pedestrian load, its probabilistic description remains scarce in literature. The present work aims at contributing to the probabilistic evaluation of the pedestrian traffic across footbridges. First, a categorized state of the art focused on sources of uncertainty is provided. Second, a new modeling framework for the probabilistic evaluation of pedestrian traffic is introduced in general and conceptual terms. The framework is conceived in analogy to the approach developed in another engineering field, i.e. wind engineering, on the basis of the phenomenological features of the pedestrian traffic. In order to put the framework in practice, each of its main modeling components is specified. We introduce a statistic approach to evaluate the incoming traffic and a microscopic traffic model to simulate the propagation along the footbridge of the uncertain pedestrian entrance. In order to prove its technical feasibility, the proposed framework is finally applied to an ensemble of real world crowd events and to two ideal footbridges with differently shaped walkway. As a final result, the pedestrian density along the footbridge is described as a random field in terms of its joint and unconditioned probability density functions and correlation lengths
Multiscale probabilistic evaluation of the footbridge crowding. Part 1: Incoming Pedestrian density
No full textThe issue of human-induced load and related mechanical performance has become one of the leading research topics in structural dynamics during the last decade. Although the concept of variability and uncertainty is well developed in structural dynamics disciplines such as wind, wave and earthquake engineering, most of the human-induced force models developed so far in structural engineering are deterministic, despite the intrinsic randomness of the crowd behaviour. The probabilistic models proposed in the last years have recognized two main sources of uncertainties, namely the structural system and the human-induced force. The pedestrian-related random variables usually considered in the cited force models are walking frequency, step length, free walking speed, single pedestrian force magnitude and body weight. According to the authors, another source of uncertainty should be considered, namely the one associated to the pedestrian traffic approaching and crossing the footbridge. This may find an analogy to what is usually done in wind engineering, where uncertainties related to the incoming wind are due to the inborn variability of the latter. Pedestrian traffic uncertainty is expected to deeply affect the crowd load on the structure: the magnitude of the overall force depends on the number of incoming pedestrians, while the load spatial distribution follows from the position of each pedestrian at the footbridge entrance and subsequently along the walkway. Coherently, in this study, the uncertainty evaluation includes the description of the undisturbed incoming traffic in terms of pedestrian density and hence introduces the variability of each pedestrian position. A two parts paper follows. The current one proposes a general procedure to collect in-situ data about the incoming crowd density and extract statistics. As such measurements are currently missing, a first attempt to obtain such statistics from data available in literature is proposed. The coefficient of variation of the incoming density is obtained and compared with the one of other pedestrian-related random variables
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