Primer registro de eritrismo parcial en una especie de rana venenosa de la familia Dendrobatidae: Epipedobates darwinwallacei Cisneros-Heredia y Yánez-Muñoz, 2010

We report the first recorded case of partial erythrism in a frog belonging to the family Dendrobatidae, Mindo Poison Frog Epipedobates darwinwallacei Cisneros-Heredia and Yánez-Muñoz, 2010. In February 2019, we found an individual in the valley of Mindo, province of Pichincha, Ecuador showing dorsal surfaces uniformly orange, throat and posterior surfaces of legs black, and ventral surfaces yellow. Despite the atypic colouration, its general morphology coincides with E. darwinwallacei, and individuals with typical colouration for the species were abundant syntopically. We include photographs comparing the erythristic individual and a typical colouration frog from the same area. We provide a brief review of chromatic atypic colourations reported in Dendrobatoidea.Reportamos el primer caso de eritrismo parcial para la familia Dendrobatidae; Epipedobates darwinwallacei Cisneros-Heredia y Yánez-Muñoz, 2010, encontrado en el en el valle de Mindo, 2019, provincia de Pichincha, Ecuador. Presenta una coloración anaranjada uniforme en el dorso, garganta y superficies posteriores de las piernas negras y superficies ventrales amarillas. A pesar de presentar una coloración atípica, su morfología general coincide con E. darwinwallacei, e individuos con la coloración típica encontrados en simpatría de la especie. Incluimos un breve resumen de los reportes de coloración cromática atípica de Dendrobatoidea y evidencia fotográfica comparando el individuo con eritrismo y uno con coloración normal de la misma localidad

La productividad y competitividad en los servicios españoles : ¿cómo ha afectado la reciente crisis económico-financiera?

Este trabajo, ya revisado, será próximamente publicado por la revista ‘Ekonomiaz’El análisis de la productividad en las actividades de servicios ha sido objeto de un interesante y creciente debate a escala internacional. Por otra parte, la productividad ocupa, desde principios de los noventa, una posición central en el estudio de la competitividad internacional de las economías. Este trabajo analiza, precisamente, las relaciones que existen entre la competitividad internacional, la productividad y los costes laborales en el sector servicios de la economía española. El ejercicio que se toma como punto de partida es 1995 y el análisis abarca hasta la actualidad, lo que permite examinar el impacto que ha tenido la crisis económica en dichas variables, con un enfoque desagregado del sector servicios. Los resultados que se obtienen son relevantes, particularmente porque en algunas de las actividades de servicios se evidencia que los factores no relacionados directamente con los costes y los precios tienen un papel muy significativo. Esto permite distanciarse – al menos parcialmente - de las teorías convencionales sobre comercio internacionalSince the 90s, productivity has become a key factor in the analysis of the international competitiveness. On the other hand, the measurement and analysis of the productivity within the service sector and their heterogeneous activities has been object of an interesting and wide international debate in recent years. This paper analyses the relationship between competitiveness, productivity and labor costs in the Spanish service industries from 1995 onwards. The two main value added of this paper to the existing literature are the disaggregated analysis within services and the focus on the disparities caused by the economic crisis. The main results suggest that non cost related factors have a key role to explain the competitiveness of some service industries, partially refuting some conventional theories on international trad

The key role of the productive structure in the countercyclical productivity in Spain

One of the most controversial topics of the Spanish economy is the countercyclical behavior of its productivity, both in the expansive years and during the recent financial and economic crisis. Additionally, this countercyclical pattern is unique among the economies of its area. This letter considers one of the likely answers to this fact: the Spanish productive structure, which is characterized by sectors such as construction and some service industries

Recent cyclical movements in the Spanish productivity : an aggregate and sectoral analysis

Uno de los temas más debatidos en la economía española es el de su productividad. Mientras en la época expansiva se observó un comportamiento negativo de esta variable, en los últimos años de fuerte crisis económico-financiera su evolución ha sido mucho más positiva, al contrario de lo observado en otros países de nuestro entorno. Por esta razón, el presente trabajo trata de analizar el efecto del ciclo económico sobre nuestra productividad desde los años 80s hasta la presente crisis, usando datos de la Contabilidad Nacional Trimestral (INE) y The Conference Board, prestando particular atención en la peculiar estructura sectorial de nuestra economíaOne of the most debated themes on the Spanish economy is the one related to productivity. While negative trends were observed during the time of expansion, its evolution has become much more positive during the recent years of strong economic and financial crisis. Additionally, this behavior is contrary to that displayed by other European countries. For this reason, this paper aims to analyze the effects of the economic cycle on Spanish labor productivity from 1980 onwards, especially focusing on the characteristic industrial structure of our economy. We use data provided by the Conference Board and the Quarterly National Accounts (INE

Recent cyclical movements in the Spanish productivity : an aggregate and sectoral analysis

Uno de los temas más debatidos en la economía española es el de su productividad. Mientras en la época expansiva se observó un comportamiento negativo de esta variable, en los últimos años de fuerte crisis económico-financiera su evolución ha sido mucho más positiva, al contrario de lo observado en otros países de nuestro entorno. Por esta razón, el presente trabajo trata de analizar el efecto del ciclo económico sobre nuestra productividad desde los años 80s hasta la presente crisis, usando datos de la Contabilidad Nacional Trimestral (INE) y The Conference Board, prestando particular atención en la peculiar estructura sectorial de nuestra economíaOne of the most debated themes on the Spanish economy is the one related to productivity. While negative trends were observed during the time of expansion, its evolution has become much more positive during the recent years of strong economic and financial crisis. Additionally, this behavior is contrary to that displayed by other European countries. For this reason, this paper aims to analyze the effects of the economic cycle on Spanish labor productivity from 1980 onwards, especially focusing on the characteristic industrial structure of our economy. We use data provided by the Conference Board and the Quarterly National Accounts (INE

Linear active disturbance rejection control of the hovercraft vessel model

A linearizing robust dynamic output feedback control scheme is proposed for earth coordinate position variables trajectory tracking tasks in a hovercraft vessel model. The controller design is carried out using only position and orientation measurements. A highly simplified model obtained from flatness considerations is proposed which vastly simplifies the controller design task. Only the order of integration of the input-to-flat output subsystems, along with the associated input matrix gain, is retained in the simplified model. All the unknown additive nonlinearities and exogenous perturbations are lumped into an absolutely bounded, unstructured, vector of time signals whose components may be locally on-line estimated by means of a high gain Generalized Proportional Integral (GPI) observer. GPI observers are the dual counterpart of GPI controllers providing accurate simultaneous estimation of each flat output associated phase variables and of the exogenous and endogenous perturbation inputs. These observers exhibit remarkably convenient self-updating internal models of the unknown disturbance input vector components. These two key pieces of on-line information are used in the proposed feedback controller to conform an active disturbance rejection, or disturbance accommodation, control scheme. Simulation results validate the effectiveness of the proposed design method

Control of a DC motor using algebraic derivative estimation with real time experiments

This paper presents an experimental control scheme for DC motors which combines an overlapping implementation of the algebraic derivative estimation method and a disturbance estimator based on the aforementioned algebraic derivative method. The methodology only requires the measurement of the angular position of the motor and the voltage input to the motor. The main advantages of the proposed approach are: it is independent of the motor’s initial conditions, the methodology is robust to Coulomb friction effects, it does not require any statistical knowledge of the noises that corrupt the data, the derivative estimation process does not require initial conditions or dependence between the system input and output, and the algorithm is computed on-line and in real time. The effectiveness of the proposed controller has been verified by means of computer simulations and it has also been experimentally implemented on a laboratory prototype with excellent results in both, stabilization and trajectory tracking tasks

The cg-average tree value for games on cycle-free fuzzy communication structures

The main goal in a cooperative game is to obtain a fair allocation of the profit due the cooperation of the involved agents. The most known of these allocations is the Shapley value. This allocation considers that the communication among the players is complete. The Myerson value is a modification of the Shapley value considering a communication structure which determines the feasible bilateral relationships among the agents. This allocation of the profit is not always a stable solution. Another payoff allocation for games with a communication structure from the definition of the Shapley value is the average tree value. This one is a stable solution for any game using a cycle-free communication structure. Later fuzzy communication structures were introduced. In a fuzzy communication structure, the membership of the agents and the relationships among them are leveled. The Myerson value was extended in several different ways depending on the behavior of the agents. In this paper, the average tree value is extended to games with fuzzy communication structures taking one particular version: the Choquet by graphs (cg). We present an application to the management of an electrical network with an algorithmic implementation.Spanish Ministry of Education and Science MTM2017-83455-PAndalusian Government FQM23

Cost-allocation problems for fuzzy agents in a fixed-tree network

Cost-allocation problems in a fixed network are concerned with distributing the costs for use by a group of clients who cooperate in order to reduce such costs. We work only with tree networks and we assume that a minimum cost spanning tree network has already been constructed and now we are interested in the maintenance costs. The classic problem supposes that each agent stays for the entire time in the same node of the network. This paper introduces cost-allocation problems in a fixed-tree network with a set of agents whose activity over the nodes is fuzzy. Agent’s needs to pay for each period of time may differ. Moreover, the agents do not always remain in the same node for each period. We propose the extension of a very well-known solution for these problems: Bird’s rule.Ministerio de Economía y Competitividad MTM2017-83455-PJunta de Andalucía FQM23