Integració d’ una unitat inercial i d’ un giroscopi de fibra òptica en un robot submarí i desenvolupament d’ un sistema de posicionament dins una piscina

El Grup de Visió per Computador i Robòtica (VICOROB) del departament d'Electrònica, Informàtica i Automàtica de la Universitat de Girona investiga en el camp de la robòtica submarina. Al CIRS (Centre d’Investigació en Robòtica Submarina), laboratori que forma part del grup VICOROB, el robot submarí Ictineu és la principal eina utilitzada per a desenvolupar els projectes de recerca. Recentment, el CIRS ha adquirit un nou sistema de sensors d' orientació basat en una unitat inercial i un giroscopi de fibra òptica. Aquest projecte pretén realitzar un estudi d' aquests dispositius i integrar-los al robot Ictineu. D' altra banda, aprofitant les característiques d’aquests sensors giroscopics i les mesures d' un sonar ja integrat al robot, es vol desenvolupar un sistema de localització capaç de determinar la posició del robot en el pla horitzontal de la piscina en temps real

Learning and adaptation in physical heterogeneous teams of robots

In this paper we present a novel approach to assigning roles to robots in a team of physical heterogeneous robots. Its members compete for these roles and get rewards for them. The rewards are used to determine each agent’s preferences and which agents are better adapted to the environment. These aspects are included in the decision making process. Agent interactions are modelled using the concept of an ecosystem in which each robot is a species, resulting in emergent behaviour of the whole set of agents. One of the most important features of this approach is its high adaptability. Unlike some other learning techniques, this approach does not need to start a whole exploitation process when the environment changes. All this is exemplified by means of experiments run on a simulator. In addition, the algorithm developed was applied as applied to several teams of robots in order to analyse the impact of heterogeneity in these systems

Projecte P.I.T.O.S (Projecte d'informació telefònica d'orientació al S.A.T)

JCM és una empresa dedicada al disseny de sistemes de control d’accés. Disposa d’uns equips elèctrics amb molts paràmetres configurables, així es poden utilitzar en molts tipus d’instal•lació. Aquets paràmetres són configurables pels clients. JCM, disposa d’un servei d’atenció telefònica (SAT), que intenta donar solucions a tots els problemes que puguin sorgir als clients. Sovint, no poden donar suport als dubtes dels clients per culpa de la poca informació que reben a través del client. L'objectiu del projecte és resoldre el problema de falta d'informació i mala comunicació per millorar la qualitat del servei que ofereix el SAT. La solució, no ha d’alterar el cost de producció del producte. S’ha de tenir en compte també que els equips poden estar instal•lats en qualsevol part del món i que només es poden utilitzar recursos de fàcil accés per tots els clients. Per complir amb aquests objectius, emetrem un missatge, a través del brunzidor del equip, amb la informació de configuració de l'equip. Aquest missatge viatjarà a través de la xarxa telefònica fins al SAT. Un cop allà, el descodificarem i n'enviarem les dades a un PC perquè pugui presentar les dades sobre la configuració de una forma clara pel SAT.

Automatització d'una planta de processos químics

Resum L’any 1969 es van començar a comercialitzar els sistemes digitals programables coneguts com autòmats programables o PLC’s, utilitzats per controlar qualsevol tipus de procés industrial. Al llarg de tots aquests anys, aquests sistemes i tota la tecnologia en general han evolucionat molt, i només és qüestió de temps que la tecnologia que utilitzem avui en dia quedi obsoleta i substituïda per una de millors característiques i amb més avantatges. Aquest és el motiu de l’elaboració d’aquest treball, que com a objectiu pretén modernitzar un procés de fabricació d’una industria química que ha quedat molt limitat a causa de l’antiguitat de la instal•lació. Per dur a terme aquesta modernització, s’introdueixen sistemes de control amb majors prestacions, s’utilitzen xarxes de comunicacions per facilitar el muntatge elèctric de la instal•lació i un sistema de supervisió i adquisició de dades per poder obtenir un control més estricte del procés de fabricació i de tots els factors que intervenen. El funcionament del procés de fabricació és que a partir d’unes matèries primeres líquides emmagatzemades en dipòsits, es dosifiquin aquestes matèries en l’ordre i la quantitat desitjada dins un o diversos recipients per barrejar-les i aplicar els tractaments que siguin necessaris. Tot aquest procés està controlat per un autòmat programable, i disposa de diferents terminals operadors per poder interactuar amb el sistema. També té implementat un sistema SCADA en diversos ordinadors per aportar una visió general de la planta en temps real, un registre de dades dels paràmetres que es controlen i alhora serveix per enllaçar amb la xarxa d’ordinadors existent. Com annex d’aquest treball, es presenten els esquemes elèctrics i el programa de l’autòmat programable per veure totes les característiques elèctriques dels dispositius i el mètode de funcionament del procés. S’ha aconseguit donar un salt tecnològic i poder gaudir de tots els avantatges que ofereixen les noves tecnologies, que com a resultat s’ha optimitzat i millorat el procés de fabricació. De totes les conclusions, la més destacada és la d’haver dissenyat un sistema de control basat en una estructura descentralitzada molt flexible, que es pot expandir i adaptar fàcilment als possibles canvis.

My News, la hemeroteca digital de la prensa española

My News, un servicio de información de prensa desarrollado en España que ofrece el texto completo de diversas publicaciones, en especial de medios de prensa escrita de ámbito nacional, presenta un interfaz renovado con nuevas funcionalidades. Se describen sus orígenes, evolución y características actuales y se analizan las nuevas prestaciones de búsqueda en su hemeroteca y de seguimiento de prensa y creación de alertas.

On-line event detection by recursive dynamic principal component analysis and gas sensor arrays under drift conditions

Leakage detection is an important issue in many chemical sensing applications. Leakage detection hy thresholds suffers from important drawbacks when sensors have serious drifts or they are affected by cross-sensitivities. Here we present an adaptive method based in a Dynamic Principal Component Analysis that models the relationships between the sensors in the may. In normal conditions a certain variance distribution characterizes sensor signals. However, in the presence of a new source of variance the PCA decomposition changes drastically. In order to prevent the influence of sensor drifts the model is adaptive and it is calculated in a recursive manner with minimum computational effort. The behavior of this technique is studied with synthetic signals and with real signals arising by oil vapor leakages in an air compressor. Results clearly demonstrate the efficiency of the proposed method.

The accumulation of reproductive incompatibilities in African cichlid fish.

The rate at which different components of reproductive isolation accumulate with divergence time between species has only been studied in a limited, but growing, number of species. We measured premating isolation and hybrid inviability at four different ontogenetic stages from zygotes to adults in interspecific hybrids of 26 pairs of African cichlid species, spanning the entire East African haplochromine radiation. We then used multiple relaxed molecular clock calibrations to translate genetic distances into absolute ages to compare evolutionary rates of different components of reproductive isolation. We find that premating isolation accumulates fast initially but then changes little with increasing genetic distance between species. In contrast, postmating isolation between closely related species is negligible but then accumulates rapidly, resulting in complete hybrid inviability after 4.4/8.5/18.4 million years (my). Thus, the rate at which complete intrinsic incompatibilities arise in this system is orders of magnitude lower than rates of speciation within individual lake radiations. Together these results suggest divergent ecological adaptations may prevent populations from interbreeding and help maintain cichlid species diversity, which may be vulnerable to environmental degradation. By quantifying the capacity to produce viable hybrids between allopatric, distantly related lineages our results also provide an upper divergence time limit for the "hybrid swarm origin" model of adaptive radiation.

Optimal dividend strategies for a compound Poisson risk process under transaction costs and power utility

We characterize the value function of maximizing the total discounted utility of dividend payments for a compound Poisson insurance risk model when strictly positive transaction costs are included, leading to an impulse control problem. We illustrate that well known simple strategies can be optimal in the case of exponential claim amounts. Finally we develop a numerical procedure to deal with general claim amount distributions.

Barnbyn Skå (Skå, la vila dels infants) 1947-1972: L’experiència terapèutica de Gustav Jonsson amb infants «irrecuperables»

The article presents the trajectory of the Swedish psychiatrist Gustav Jonsson (1907-1994) who, in the 1940s, revolutionised the therapeutic and educational treatment of children and young people, considered irreclaimable from the social point of view, who were committed to educational institutions. It analyses the social development of the Welfare State in Sweden, the legal framework of child protection, as well as the context of Swedish residential care centres for children and young people in the first half of the 20th century in order to go further into the psychological and educational work conducted with the Barnbyn Skå group. Jonsson redirected the analysis of violent behaviours that were manifest in these children and young people which made them intractable from the educational point of view and established elements of psychoanalytical understanding, based on a systemic approach in which the family context became essential in order to understand the children’s difficulties. Barnbyn Skå was the centre which, under the guidance of Jonsson, developed this new therapeutic and pedagogic approach. The educational work carried out there exceeded the traditional model in terms of control and surveillance. The methods were considered radical from within pedagogy and caused great controversy which led the centre to continuous investigations on behalf of the Social Services of Stockholm between 1960 and 1970. For several decades Barnbyn Skå has been considered a pioneering experience in the field of Scandinavian child psychiatry.

09008-005 Hewitt Creek Final Report

The primary goal of the Hewitt Creek watershed council is to have Hewitt-Hickory Creek removed from the Iowa impaired waters (303d) list. Hewitt Creek watershed, a livestock dense 23,005 acre sub-watershed of the Maquoketa River Basin, is 91.2% agricultural and 7.5% woodland. Since 2005, sixty-seven percent of 84 watershed farm operations participated in an organized watershed improvement effort using a performance­ based watershed management approach, reducing annual sediment delivery to the stream by 4,000 tons. Watershed residents realize that water quality improvement efforts require a long-term commitment in order to meet their watershed improvement goals and seek funding for an additional five years to continue their successful watershed improvement project. Cooperators will be provided incentives for improved environmental performance, along with incentives and technical support to address feedlot runoff issues and sub-surface nitrate-nitrogen loss. The Phosphorus Index, Soil Conditioning Index and cornstalk nitrate test will be used by producers as measures of performance to refine nutrient and soil loss management and to determine effective alternatives to reduce nutrient and sediment delivery. Twenty-five livestock operations will improve feedlot runoff control systems and five sub-surface bioreactors will be installed to reduce nitrate delivery from priority tile-drained fields. The Hewitt Creek council will seek additional cost-share funding for high-cost feedlot runoff control structures, sediment control basins and stream bank stabilization projects.

Using music as a signal for biofeedback

Studies on the potential benefits of conveying biofeedback stimulus using a musical signal have appeared in recent years with the intent of harnessing the strong effects that music listening may have on subjects. While results are encouraging, the fundamental question has yet to be addressed, of how combined music and biofeedback compares to the already established use of either of these elements separately. This experiment, involving young adults (N = 24), compared the effectiveness at modulating participants' states of physiological arousal of each of the following conditions: A) listening to pre-recorded music, B) sonification biofeedback of the heart rate, and C) an algorithmically modulated musical feedback signal conveying the subject's heart rate. Our hypothesis was that each of the conditions (A), (B) and (C) would differ from the other two in the extent to which it enables participants to increase and decrease their state of physiological arousal, with (C) being more effective than (B), and both more than (A). Several physiological measures and qualitative responses were recorded and analyzed. Results show that using musical biofeedback allowed participants to modulate their state of physiological arousal at least equally well as sonification biofeedback, and much better than just listening to music, as reflected in their heart rate measurements, controlling for respiration-rate. Our findings indicate that the known effects of music in modulating arousal can therefore be beneficially harnessed when designing a biofeedback protocol.

Towards Machine Consciousness: Grounding Abstract Models as pi-Processes

We present a two-level model of concurrent communicating systems (CCS) to serve as a basis formachine consciousness. A language implementing threads within logic programming is ¯rstintroduced. This high-level framework allows for the de¯nition of abstract processes that can beexecuted on a virtual machine. We then look for a possible grounding of these processes into thebrain. Towards this end, we map abstract de¯nitions (including logical expressions representingcompiled knowledge) into a variant of the pi-calculus. We illustrate this approach through aseries of examples extending from a purely reactive behavior to patterns of consciousness.

Power quality improving with virtual flux-based voltage source line converter

Line converters have become an attractive AC/DC power conversion solution in industrial applications. Line converters are based on controllable semiconductor switches, typically insulated gate bipolar transistors. Compared to the traditional diode bridge-based power converters line converters have many advantageous characteristics, including bidirectional power flow, controllable de-link voltage and power factor and sinusoidal line current. This thesis considers the control of the lineconverter and its application to power quality improving. The line converter control system studied is based on the virtual flux linkage orientation and the direct torque control (DTC) principle. A new DTC-based current control scheme is introduced and analyzed. The overmodulation characteristics of the DTC converter are considered and an analytical equation for the maximum modulation index is derived. The integration of the active filtering features to the line converter isconsidered. Three different active filtering methods are implemented. A frequency-domain method, which is based on selective harmonic sequence elimination, anda time-domain method, which is effective in a wider frequency band, are used inharmonic current compensation. Also, a voltage feedback active filtering method, which mitigates harmonic sequences of the grid voltage, is implemented. The frequency-domain and the voltage feedback active filtering control systems are analyzed and controllers are designed. The designs are verified with practical measurements. The performance and the characteristics of the implemented active filtering methods are compared and the effect of the L- and the LCL-type line filteris discussed. The importance of the correct grid impedance estimate in the voltage feedback active filter control system is discussed and a new measurement-based method to obtain it is proposed. Also, a power conditioning system (PCS) application of the line converter is considered. A new method for correcting the voltage unbalance of the PCS-fed island network is proposed and experimentally validated.