From Scale-free to Erdos-Renyi Networks

We analyze a model that interpolates between scale-free and Erdos-Renyi networks. The model introduced generates a one-parameter family of networks and allows to analyze the role of structural heterogeneity. Analytical calculations are compared with extensive numerical simulations in order to describe the transition between these two important classes of networks. Finally, an application of the proposed model to the study of the percolation transition is presented.Comment: 8 pages, 6 figure

Analysis of competitiveness in Colombian family businesses

Purpose: Building on the resource-based view and the configuration theory, the purpose of this study uses a systemic and multidimensional competitiveness index (CI) i.e. that incorporates system constraints among the 10 competitive pillars that form the index to assess the competitiveness level and the connection between competitiveness and economic performance [return on assets (ROA)] in family businesses (FBs). Design/methodology/approach: For the empirical application, the use a unique primary data set drawn from the global competitiveness project (www.gcp.org) that includes information for 77 Colombian FBs for 2017. Cluster analysis is used to evaluate the potential relationship between competitiveness, the configuration of competitive pillars and economic performance (ROA). Findings: The results for the CI show that the main competitive strengths of the analysed firms are related to the introduction of product innovations and networks (suppliers and customers), while the limited use of technologies in their operations and the low online presence are the main competitive weaknesses of these firms. Additionally, the findings of the cluster analysis reveal that different configurations of competitiveness pillars are associated with different performance levels. Therefore, the results contribute to identifying how specific strategies aimed at improving different resources or capabilities contribute to enhance business competitiveness, and ultimately, performance. Originality/value: By using an index number that takes into account the multiple interactions between resources and capabilities, the proposed analysis not only sheds light on the drivers of competitiveness i.e. resources and capabilities, and its connection to performance but also contributes to understanding the boundaries of the businesses’ competitiveness system, as well as the strategies that can potentially enhance competitiveness, and subsequently, business performance.Peer ReviewedPreprin

Hallucinating dense optical flow from sparse lidar for autonomous vehicles

© 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.In this paper we propose a novel approach to estimate dense optical flow from sparse lidar data acquired on an autonomous vehicle. This is intended to be used as a drop-in replacement of any image-based optical flow system when images are not reliable due to e.g. adverse weather conditions or at night. In order to infer high resolution 2D flows from discrete range data we devise a three-block architecture of multiscale filters that combines multiple intermediate objectives, both in the lidar and image domain. To train this network we introduce a dataset with approximately 20K lidar samples of the Kitti dataset which we have augmented with a pseudo ground-truth image-based optical flow computed using FlowNet2. We demonstrate the effectiveness of our approach on Kitti, and show that despite using the low-resolution and sparse measurements of the lidar, we can regress dense optical flow maps which are at par with those estimated with image-based methods.Peer ReviewedPostprint (author's final draft

Rpd3L and Hda1 histone deacetylases facilitate repair of broken forks by promoting sister chromatid cohesion

Genome stability involves accurate replication and DNA repair. Broken replication forks, such as those encountering a nick, lead to double strand breaks (DSBs), which are preferentially repaired by sister-chromatid recombination (SCR). To decipher the role of chromatin in eukaryotic DSB repair, here we analyze a collection of yeast chromatin-modifying mutants using a previously developed system for the molecular analysis of repair of replication-born DSBs by SCR based on a mini-HO site. We confirm the candidates through FLP-based systems based on a mutated version of the FLP flipase that causes nicks on either the leading or lagging DNA strands. We demonstrate that Rpd3L and Hda1 histone deacetylase (HDAC) complexes contribute to the repair of replication-born DSBs by facilitating cohesin loading, with no effect on other types of homology-dependent repair, thus preventing genome instability. We conclude that histone deacetylation favors general sister chromatid cohesion as a necessary step in SCR

Students' perspective on on-line college education in the field of journalism

The advance in new technologies has changed the educational model considerably. On-line education has arrived with a bang at university and those degree courses linked to the field of communication have adopted this type of technologies. In just a few years, the number of courses available in the communication field that include on-line subjects has multiplied. It seems that this tendency of proliferation will continue due to a high demand for degrees in the communication field as well as the possibility of completing these degrees on-line. This paper shows the perspective that on-line journalism students at the Rey Juan Carlos University in Madrid have on their studies. The results of a survey of students of the different courses that include the qualification allow us to gain a perspective of their experiences at the beginning and end of the studies. The questionnaire asks about socio-demographic traits from which we draw a sociological profile of on-line journalism student. It also delves into the motivations and expectations surrounding the decision to enrol in this mode and in its assessment both in terms of learning and the relationship between peers and teachers. Some of the conclusions point to the positive attitude of students and a satisfactory evaluation by the students

Gender diversity in the board, women’s leadership and business performance

Purpose: This paper investigates how gender diversity in top management—i.e., boardroom and top management positions—impacts business performance among Colombian public businesses. Design/methodology/approach: Building on the Upper Echelon theory which emphasizes that gender in an important characteristic that influences top management’s decision making, we employ panel data models on a sample of 54 Colombian public businesses for the period 2008-2015 to test the proposed hypotheses relating gender diversity and subsequent business performance. Findings: The results support that gender diversity is positively associated with subsequent business performance. More concretely, we find that the relationship between gender diversity at the top of the corporate hierarchy—in our case, as CEO and in the top management team—and subsequent performance becomes more evident when performance is linked to business operations (ROA), while the positive effect of women’s representation in the boardroom and subsequent performance is significant when performance is measured via shareholder-oriented metrics (ROE). Originality/value: Few studies have addressed the role of gender diversity on performance in developing economies. This study contributes to better understand how gender diversity impacts performance in contexts where women are underrepresented in the top management, and where the appointment of women directors or managers is not driven by regulatory pressures.Peer ReviewedPostprint (author's final draft

Improved routing strategies for Internet traffic delivery

We analyze different strategies aimed at optimizing routing policies in the Internet. We first show that for a simple deterministic algorithm the local properties of the network deeply influence the time needed for packet delivery between two arbitrarily chosen nodes. We next rely on a real Internet map at the autonomous system level and introduce a score function that allows us to examine different routing protocols and their efficiency in traffic handling and packet delivery. Our results suggest that actual mechanisms are not the most efficient and that they can be integrated in a more general, though not too complex, scheme.Comment: Final versio

El delicte de conducció sota la influència de begudes alcohòliques. Art. 379.2 CP

Treballs Finals del Màster de Direcció Estratègica de Seguretat i Policia, Facultat de Dret, Universitat de Barcelona, Curs: 2013-2014, Tutor: Sergi Cardenal MontravetaActualment, l'accidentalitat viària és una de les principals causes de mortalitat. Any rere any produeix un gran número de morts a més d'un elevat volum de ferits i lesionats comportant grans pèrdues personals, materials i econòmiques. Darrerament, dos dels principals motius destacats en els accidents de trànsit han sigut lexcés de velocitat i la conducció sota els efectes de begudes alcohòliques i/o substàncies estupefaents provocant canvis en la legislació i incorporant taxes quantitatives fàcilment mesurables que delimiten de forma clara la frontera entre el procediment purament administratiu i el pas a la via del dret penal. A més a més, l’afectació i l’impacte global que ocasionen aquests tipus de conductes a la seguretat col·lectiva ha fet que en els últims anys la sinistralitat es posi en primer pla de debat de l’opinió pública i mediàtica, i conseqüentment, entri a formar part de l’objectiu primordial de l’agenda política. Arran de les últimes modificacions legislatives es pot observar que com a resposta a les demandes socials en matèria de seguretat viària es recorre a l’eina del dret penal, ampliant el tipus de delictes existents, i transformant en part el seu caràcter clàssic de mesura més contundent per tal d’avançar les barreres de protecció davant de riscos concebuts com a insuportables, afavorint l’aplicació d’una nova concepció més moderna de les normes penals. Tenint en compte els citats factors, la gran quantitat de recursos humans i materials que es destinen a la persecució de determinades conductes prohibides i la pròpia observació professional durant els anys que porto treballant com a agent de policia, he considerat oportú realitzar aquest treball centrant-me en l'estudi del delicte de conducció sota la influència de begudes alcohòliques..

De Dante y otras vite.

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