Reliable and timely event notification for publish/subscribe services over the internet

The publish/subscribe paradigm is gaining attention for the development of several applications in wide area networks (WANs) due to its intrinsic time, space, and synchronization decoupling properties that meet the scalability and asynchrony requirements of those applications. However, while the communication in a WAN may be affected by the unpredictable behavior of the network, with messages that can be dropped or delayed, existing publish/subscribe solutions pay just a little attention to addressing these issues. On the contrary, applications such as business intelligence, critical infrastructures, and financial services require delivery guarantees with strict temporal deadlines. In this paper, we propose a framework that enforces both reliability and timeliness for publish/subscribe services over WAN. Specifically, we combine two different approaches: gossiping, to retrieve missing packets in case of incomplete information, and network coding, to reduce the number of retransmissions and, consequently, the latency. We provide an analytical model that describes the information recovery capabilities of our algorithm and a simulation-based study, taking into account a real workload from the Air Traffic Control domain, which evidences how the proposed solution is able to ensure reliable event notification over a WAN within a reasonable bounded time window. © 2013 IEEE

The hermeneutic function of the literary work in "Cómo se hace una novela"

El objetivo de este trabajo es dar cuenta de la fecundidad que el pensamiento de Unamuno (1864-1936) presenta en torno al problema hermenéutico. Para ello se tomará como eje la obra Cómo se hace una novela (1926-7), donde el pensador bilbaíno expone sus ideas en torno a la cuestión de la escritura y la recepción de la obra literaria. El estudio de la obra en cuestión y la referencia a muchas de sus otras obras estará atravesado por las nociones que acuñara Ricoeur de “distanciamiento” y “apropiación” del mundo del texto. La importancia que cobra en Unamuno el receptor de la obra, anticipándose a las ulteriores teorías de la recepción, nos lleva a ver qué entiende éste por “comprensión”, y cuál es el papel que esa noción juega en sus concepciones filosófico-literarias. Finalmente, a partir de este “distanciamiento” y “apropiación” de la obra que propone Unamuno al lector, le será posible al receptor, la proyección de un mundo.The purpose of this work is realize of the fecundity that Unamuno’s (1864-1936) thought presents concerning the hermeneutic problem. For it the work will take as a point of item Cómo se hace una novela (1926-7), where Unamuno exposes his ideas concerning the question of the writing and the receipt of the literary work. The study of the work in question and the reference too many of his other works will be crossed by the notions that there was coining Ricoeur of “distancing” and “appropriation” of the world of the text. The importance that takes in Unamuno the receiver of the work, being anticipated to the subsequent theories of the receipt, leads us to seeing what deals this one for “comprehension”, and which is the role that this notion plays in his philosophical - literary conceptions. Finally, from this “distancing” and “appropriation” of the work that Unamuno proposes to the reader will be possible to the receiver, the projection of one world

A bi-level model for the design of dynamic electricity tariffs with demand-side flexibility

This paper addresses the electricity pricing problem with demand-side flexibility. The interaction between an aggregator and the prosumers within a coalition is modeled by a Stackelberg game and formulated as a mathematical bi-level program where the aggregator and the prosumer, respectively, play the role of upper and lower decision makers with conflicting goals. The aggregator establishes the pricing scheme by optimizing the supply strategy with the aim of maximizing the profit, prosumers react to the price signals by scheduling the flexible loads and managing the home energy system to minimize the electricity bill. The problem is solved by a heuristic approach which exploits the specific model structure. Some numerical experiments have been carried out on a real test case. The results provide the stakeholders with informative managerial insights underlining the prominent roles of aggregator and prosumers

A quantitative trait locus analysis of personality in wild bighorn sheep

Acknowledgments This study was supported by an Alberta Conservation Association grant to JP and Natural Sciences and Engineering Council of Canada (NSERC) discovery grants to DWC, MF and Fanie Pelletier. JP was supported by postdoctoral fellowships from NSERC and the European Research Council. We thank Joshua Miller for his help with reconstructing the Ram Mountain pedigree. We thank Jon Jorgenson and the numerous graduate students and field assistants who worked at Ram Mountain over the years.Peer reviewedPublisher PD

The optimal management of the prosumer's resources via stochastic programming

This paper deals with the optimal home energy management problem faced by a smart prosumer equipped with PV panels and storage systems. The stochastic programming framework is adopted with the aim of explicitly accounting for the inherent uncertainty affecting the main problem parameters (i.e. generation from renewable energy sources and demands). The problem provides the prosumer with the optimal scheduling of the shiftable loads and operations of the available storage systems that minimizes the expected overall electricity cost. Preliminary results, collected on three different categories of residential prosumers, have shown the effectiveness of the proposed approach in terms of cost saving. Keywords: Home energy management systems, Optimal scheduling, Renewable energy, Stochastic programming, Storage devic

A Selective Scheduling Problem with Sequence-dependent Setup Times: A Risk-averse Approach

This paper addresses a scheduling problem with parallel identical machines and sequence-dependent setup times in which the setup and the processing times are random parameters. The model aims at minimizing the total completion time while the total revenue gained by the processed jobs satisfies the manufacturer’s threshold. To handle the uncertainty of random parameters, we adopt a risk-averse distributionally robust approach developed based on the Conditional Value-at-Risk measure hedging against the worst-case performance. The proposed model is tested via extensive experimental results performed on a set of benchmark instances. We also show the efficiency of the deterministic counterpart of our model, in comparison with the state-of-the-art model proposed for a similar problem in a deterministic context