Development of a fuzzy control based self-adaptive system for energy saving in constrained networks for the Internet of Things

Las redes del futuro, incluyendo las redes de próxima generación, tienen entre sus objetivos de diseño el control sobre el consumo de energía y la conectividad de la red. Estos objetivos cobran especial relevancia cuando hablamos de redes con capacidades limitadas, como es el caso de las redes de sensores inalámbricos (WSN por sus siglas en inglés). Estas redes se caracterizan por estar formadas por dispositivos de baja o muy baja capacidad de proceso y por depender de baterías para su alimentación. Por tanto la optimización de la energía consumida se hace muy importante. Son muchas las propuestas que se han realizado para optimizar el consumo de energía en este tipo de redes. Quizás las más conocidas son las que se basan en la planificación coordinada de periodos de actividad e inactividad, siendo una de las formas más eficaces para extender el tiempo de vida de las baterías. La propuesta que se presenta en este trabajo se basa en el control de la conectividad mediante una aproximación probabilística. La idea subyacente es que se puede esperar que una red mantenga la conectividad si todos sus nodos tienen al menos un número determinado de vecinos. Empleando algún mecanismo que mantenga ese número, se espera que se pueda mantener la conectividad con un consumo energético menor que si se empleara una potencia de transmisión fija que garantizara una conectividad similar. Para que el mecanismo sea eficiente debe tener la menor huella posible en los dispositivos donde se vaya a emplear. Por eso se propone el uso de un sistema auto-adaptativo basado en control mediante lógica borrosa. En este trabajo se ha diseñado e implementado el sistema descrito, y se ha probado en un despliegue real confirmando que efectivamente existen configuraciones posibles que permiten mantener la conectividad ahorrando energía con respecto al uso de una potencia de transmisión fija. ABSTRACT. Among the design goals for future networks, including next generation networks, we can find the energy consumption and the connectivity. These two goals are of special relevance when dealing with constrained networks. That is the case of Wireless Sensors Networks (WSN). These networks consist of devices with low or very low processing capabilities. They also depend on batteries for their operation. Thus energy optimization becomes a very important issue. Several proposals have been made for optimizing the energy consumption in this kind of networks. Perhaps the best known are those based on the coordinated planning of active and sleep intervals. They are indeed one of the most effective ways to extend the lifetime of the batteries. The proposal presented in this work uses a probabilistic approach to control the connectivity of a network. The underlying idea is that it is highly probable that the network will have a good connectivity if all the nodes have a minimum number of neighbors. By using some mechanism to reach that number, we hope that we can preserve the connectivity with a lower energy consumption compared to the required one if a fixed transmission power is used to achieve a similar connectivity. The mechanism must have the smallest footprint possible on the devices being used in order to be efficient. Therefore a fuzzy control based self-adaptive system is proposed. This work includes the design and implementation of the described system. It also has been validated in a real scenario deployment. We have obtained results supporting that there exist configurations where it is possible to get a good connectivity saving energy when compared to the use of a fixed transmission power for a similar connectivity.

Trusted Tiny Things : Making Devices in Smart Cities More Transparent

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Do Things Change in Therapy That Are Not Measured By Self-report Instruments?

This study investigates a new way of assessing change in psychotherapy, with the goal of decreasing the schism in the field of psychology between research and clinical practice. Change in psychotherapy was assessed in clients presenting with depressive symptoms who were seeking therapy at the Professional Psychology Center (PPC) at the University of Denver. Prior to beginning treatment, the subjects completed the Beck Depression Inventory- II (BDI-II) and the Symptom Checklist-90-R (SCL-90), and were also assessed by independent clinicians using the Shedler-Westen Assessment Procedure II (SWAP-II). Six to nine months later, after completing at least 12 psychotherapy sessions (range 12-21 sessions), the assessment procedure was repeated.There were no significant differences pre- to post-treatment on any measure. However, two subjects in the sample appeared to benefit from treatment, as assessed by both the self-report measures and the SWAP-II. The findings for these two subjects suggest that the SWAP-II can provide a greater depth of understanding about what can change in therapy than self-report measures alone. Possible reasons for the lack of treatment effects in the larger sample are discussed.

A Return to Little Things: Stories on Motherhood and Mistakes

A Return to Little Things includes three nonfiction pieces that revolve around the mistakes made by mothers and daughters. The collection investigates the idea that our lives are a sum total of the choices we have made. The essays directly address three specific situations that touch on the themes of motherhood, choices, and the human inclination to recall them with bitterness, and offer proof that time often allows us to move forward to forgiveness. Using humor and acceptance, the narrator is led through a labyrinth of emotions to come to peace with these choices. The stories serve as reminders that there are no mistakes, only lessons, and we must seek to understand them to live happy lives. This manuscript is a work in progress.

Some Acct. of Sev'l things relating to the College contain'd in ye Charter Laws &c with references to the originals (manuscript partial copy), [1721 October]

Two octavo-sized leaves with four half-page columns containing a handwritten copy, made by President Leverett, of an October 17, 1721 a paper composed by Nicholas Sever and William Welsteed to Judge Samuel Sewall.

An Acct of Several things relating to ye Coll: contained in ye Charter Laws &c: w'th references to the Originals (manuscript copy), 1721 October 17

Two folio-sized leaves containing a three-page handwritten report sent by Nicholas Sever and William Welsteed to Judge Samuel Sewall outlining the historical precedence for the Tutors' claims. The body of the text begins, "What we assert in ye first place..."

Five things we need to know about the on-demand economy. CEPS Essay No. 21/8 January 2016

The last few years have witnessed the exponential growth of platforms like Uber and Airbnb and the creation of countless other less well-known examples. The expansion of the on-demand economy puts huge pressure on regulators to adapt it to the existing frameworks for labour and taxation. The rapid growth of the sector also divides experts: it is seen by many as threat for working conditions, and by others as an incredible opportunity. The purpose of this essay is to take a balanced perspective on what we know about the on-demand economy and what needs further investigation. More research is needed on the individual cases before one can draw conclusions on how this new sector works. The political economy of the sector is made even more interesting by the fact that the technology is developing faster than the regulation. Yet, our plea to policy-makers is to refrain from legislating too early and to take the time to understand how the supply and the demand of these services behave and their equilibrium.

La sicurezza nell'Internet of Things

Un analisi delle problematiche sulla sicurezza e sulla privacy riguardante l'IoT suddivisa nei Layer dei quali si compone, dai piccoli sensori ai fornitori di servizi nel Cloud. In coda anche una breve trattazione delle emergenti questioni etiche e sociali.

The Slow Regard of Silent Things - Proposta di traduzione e commento

In questo elaborato si propone una traduzione per il primo capitolo del romanzo "The Slow Regard of Silent Things", un testo di narrativa fantasy per young adults. Si analizzano in oltre le particolarità del testo e alcuni punti critici della traduzione alla luce di un percorso teorico basato sul lavoro di studiosi dal diciannovesimo secolo fino ai giorni nostri.

A history of everyday things in England, 1066-1799 /

Mode of access: Internet.

First things and last : the story of birth and death certificates.

Cover title.