Integration of streaming services and TCP data transmission in the Internet

We study in this paper the integration of elastic and streaming traffic on a same link in an IP network. We are specifically interested in the computation of the mean bit rate obtained by a data transfer. For this purpose, we consider that the bit rate offered by streaming traffic is low, of the order of magnitude of a small parameter \eps \ll 1 and related to an auxiliary stationary Markovian process (X(t)). Under the assumption that data transfers are exponentially distributed, arrive according to a Poisson process, and share the available bandwidth according to the ideal processor sharing discipline, we derive the mean bit rate of a data transfer as a power series expansion in \eps. Since the system can be described by means of an M/M/1 queue with a time-varying server rate, which depends upon the parameter \eps and process (X(t)), the key issue is to compute an expansion of the area swept under the occupation process of this queue in a busy period. We obtain closed formulas for the power series expansion in \eps of the mean bit rate, which allow us to verify the validity of the so-called reduced service rate at the first order. The second order term yields more insight into the negative impact of the variability of streaming flows

Congestion analysis of unsignalized intersections

This paper considers an unsignalized intersection used by two traffic streams. A stream of cars is using a primary road, and has priority over the other, low-priority, stream. Cars belonging to the latter stream cross the primary road if the gaps between two subsequent cars on the primary road is larger than their critical headways. Questions that naturally arise are: given the arrival pattern of the cars on the primary road, what is the maximum arrival rate of low-priority cars such that the number of such cars remains stable? In the second place, what can be said about the delay experienced by a typical car at the secondary road? This paper addresses such issues by considering a compact model that sheds light on the dynamics of the considered unsignalized intersection. The model, which is of a queueing-theoretic nature, reveals interesting insights into the impact of the user behavior on the above stability and delay issues. The contribution of this paper is twofold. First, we obtain new results for the aforementioned model with driver impatience. Secondly, we reveal some surprising aspects that have remained unobserved in the existing literature so far, many of which are caused by the fact that the capacity of the minor road cannot be expressed in terms of the \emph{mean} gap size; instead more detailed characteristics of the critical headway distribution play a role.Comment: This paper appeared in the proceedings of the 8th International Conference on Communication Systems and Networks (COMSNETS), 5-10 Jan. 2016. A related but more extended paper which analyses a more general model than the one in the present paper can be also found on arXiv:1802.0673

Mancebas de españoles, madres de mestizos. Imágenes de la mujer indígena en el Perú colonial temprano

25 p.Como sabemos, una buena parte de los hogares que los conquistadores y primeros colonos constituyeron en Indias se sustentaron en sus inicios y por un tiempo más o menos prolongado, según los casos, en la convivencia con una y a veces varias mujeres indígenas. Por lo general, estas uniones de hecho parecen haberse quebrado con la incorporación al hogar, en calidad de esposa legítima, de una mujer de ascendencia europea, ya fuera peninsular, criolla o incluso mestiza. Su irrupción supuso el desplazamiento de aquellas primeras mujeres, que o bien tuvieron que abandonar la casa, muchas veces dejando en ella a sus hijos mestizos, o bien pasaron a ocupar en la intimidad cuartos traseros y a posiciones de segundo plano cara a la vida pública.Peer reviewe

Relaciones sexuales y afectivas en tiempos de conquista. La Española

pags.237-25

Mestizos, mulatos y zambaigos (Virreinato del Perú, siglo XVI)

13 p.Peer reviewe

Why are undergraduate emerging adults anxious and avoidant in their romantic relationships? The role of family relationships

The exploration of and search for romantic relationships is one of the developmental tasks that characterise emerging adulthood, a new developmental phase halfway between adolescence and full adulthood. This study aims to explore, in a Mediterranean country, the existing relationships between the subjective perception of some parental behaviour and the anxiety and avoidance dimensions of attachment during emerging adulthood. To do so, 1,502 university students (903 women and 599 men) aged between 18 and 29 (M = 20.32 and SD = 2.13) completed a self-report questionnaire. The results revealed that perceived family support and perceived parental warmth were negatively associated with the avoidance and anxiety dimensions. In contrast, perceived parental control (both behavioural and psychological) was found to be positively associated with both attachment dimensions. Perceived behavioural control was also found to play a moderator role between perceived parental warmth and romantic attachment anxiety. Only in cases in which emerging adults of our sample perceived low levels of behavioural control was warmth found to be negatively associated with anxiety. The main conclusion of this work is the negative impact that parental control seems to have on romantic attachment during emerging adulthood. The results are discussed with a focus on the continuing importance of the family context in relation to the completion of developmental tasks, even during emerging adulthood.Ministerio de Economía y Competitividad EDU2013-45687-RMinisterio de Ciencia, Innovación y Universidades RTI2018-097405-B-I0

Note on the GI/GI/1 queue with LCFS-PR observed at arbitrary times

Consider the GI/GI/1 queue with the Last-Come First-Served Preemptive-Resume service discipline. We give intuitive explanations for (i) the geometric nature of the stationary queue length distribution and (ii) the mutual independence of the residual service requirements of the customers in the queue, both considered at arbitrary time points. These distributions have previously been established in the literature by either first considering the system at arrival instants or using balance equations. Our direct arguments provide further understanding of (i) and (ii)