Análisis de los factores determinantes del nivel de innovación en el sector hotelero español. Estudio según variable de segmentación

La investigación que se presenta en este trabajo estudia las relaciones que se producen entre ciertos factores determinantes del Proceso de Dirección Estratégica y la innovación en las organizaciones hoteleras con actividad en nuestro país, así como analiza la influencia del nivel de innovación sobre la ventaja competitiva y los resultados organizativos. El trabajo pretende aportar una serie de contribuciones tanto en el ámbito teórico como en el práctico. En el ámbito teórico, la novedad estriba en presentar las conexiones entre los factores que determinan el Proceso de Dirección Estratégica y su impacto en el nivel de innovación, que aunque presentan puntos de contacto evidentes, hasta el momento no han sido sometidos a un tratamiento integrador por parte de la literatura especializada. Para ello, el enfoque teórico basado en los Recursos y Capacidades constituye un marco teórico influyente y adecuado para entender esta conexión. Empíricamente, el análisis de las interrelaciones estratégicas entre ciertos factores del Modelo de Dirección Estratégica y el grado de innovación, así como su impacto en los resultados empresariales, ayudará a destacar la importancia de tratar la gestión de la innovación como una estrategia en sí misma, y a introducirlas en el modelo de pensamiento estratégico de las cadenas hoteleras con actividad en nuestro país.The research presented in this work in this work bases on the study of the relations which the determining factors of the Process of Strategic Management and Innovation in the hotel organizations in our country, as well as to analyze the influence of the innovation level on the competitive advantage and on the organizational results. Overall, this study aims to provide a range of contributions in both theoretical and practical. In the theoretical, the novelty lies in presenting the connections among the factors that determine the strategic direction process and its impact on the level of innovation, but have obvious points of contact, so far have not been subjected to integrative by the literature. For this, the theoretical approach based on the Resources and Capabilities is an influential and adequate theoretical framework for understanding this connection. Empirically, the analysis of the strategic interrelations between certain factors of the Model of Strategic Management and the degree of innovation, as well as its impact in the enterprise results, will help to emphasize the importance of dealing with the management the innovation like a strategy in itself, and to introduce them in the model of strategic thought of the hotel chains with activity in our country

HÁBITOS ALIMENTARIOS DE ANOURA GEOFFROYI (CHIROPTERA: PHYLLOSTOMIDAE) EN IXTAPAN DEL ORO, ESTADO DE MÉXICO

We describe the feeding habits of the bat Anoura geoffroyi in the Seasonal Dry Tropical Forest at Ixtapan del Oro, Estado de Mexico. During a year, hair remainders and fecal samples from 153 individuals were collected every two weeks. We found just pollen grains and insect’s debris in the samples. The pollen morphotypes correspond to plants that are frequently visited for nectar-feeding bats, the genus Ipomoea outstands for its frequency and it is the first report of Brugmansia candida, Stenocereus sp. and a species from Asteraceae family in the A. geoffroyi diet. The plants determined from pollen morphotypes present chiropterophilous syndrome characteristics, nevertheless, they are also pollinated by moths. Reason why and considering the morphological adaptations of A. geoffroyi for nectar consumption and the fact that 95% of the insects debris found in the samples correspond to lepidopterons, we could consider the species in the study place like a nectar-feeding bat that also has the capacity to eat lepidopterons associated to the flowers where this bat forages.Se describen los hábitos alimentarios del murciélago Anoura geoffroyi en la Selva Baja Caducifolia de Ixtapan del Oro, Estado de México, para ello se colectaron quincenalmente durante un año muestras de residuos del pelaje y heces de 153 individuos. Se observó sólo granos de polen y restos de insectos en las muestras. Los morfotipos de polen encontrados corresponden a plantas que son frecuentadas por murciélagos nectarívoros, destaca por su frecuencia el género Ipomoea y se reporta por primera vez la presencia de Brugmansia candida, Stenocereus sp. y una especie de la familia Asteraceae en la dieta de A. geoffroyi. Las plantas determinadas por los tipos polínicos presentan características del síndrome quiropterofílico, sin embargo, también son polinizadas por mariposas nocturnas, por lo que considerando las adaptaciones morfológicas de A. geoffroyi para el consumo de néctar y que el 95% de los restos de insectos encontrados corresponden a lepidópteros, se podría catalogar a la especie en el sitio de estudio como un murciélago nectarívoro que presenta también la capacidad de alimentarse de lepidópteros asociados a las flores que frecuenta

Modeling nonlinear power amplifiers in OFDM systems from subsampled data: a comparative study using real measurements

A comparative study among several nonlinear high-power amplifier (HPA) models using real measurements is carried out. The analysis is focused on specific models for wideband OFDM signals, which are known to be very sensitive to nonlinear distortion. Moreover, unlike conventional techniques, which typically use a single-tone test signal and power measurements, in this study the models are fitted using subsampled time-domain data. The in-band and out-of-band (spectral regrowth) performances of the following models are evaluated and compared: Saleh’s model, envelope polynomial model (EPM), Volterra model, the multilayer perceptron (MLP) model, and the smoothed piecewise-linear (SPWL) model. The study shows that the SPWL model provides the best in-band characterization of the HPA. On the other hand, the Volterra model provides a good trade-off between model complexity (number of parameters) and performance

Tratamiento de las fracturas del fémur distal en ancianos

Presentamos los resultados comparativos del tratamiento con dos métodos diferentes de 55 casos de fractura del fémur distal en pacientes ancianos. Hugo 27 pacientes que fueron tratados con el tornillo dinámico condilar (grupo A) y 28 con tracción esquelética (grupo B). Se obtuvieron resultados excelentes y buenos en el 70% del grupo quirúrgico y en el 30% del grupo no intervenido. Hubo más complicaciones en este último. Cinco pacientes fallecieron, todos ellos en el grupo B.We report the comparative results of treatment of 55 cases of fractures of the distal femur in elderly patients using two different methods. There were 27 patients treated with the dynamic condylar screw (group A), and 28 with skeletal traction (group B). excellent or good results were achieved in 70% of the operated and in 30% of the non-operated group. There were more complications in the latter. Five patients died, all of them in group B

Expresiones cerradas de capacidad de sistemas MIMO 2X2 en canales arbitrarios

Recent works have shown the potential performance MIMO systems based on dual-polarized antennas at transmitter and receiver. These works assume Rayleigh or Ricean channel models. In this paper we provide closed-form expressions of the ergodic capacity for arbitrary channels, being the Rayleigh and Ricean two particular cases. These expressions are function of the specific physical characteristics of the propagation environment and antennas, therefore they directly connect the ergodic capacity with the physical characteristics of the MIMO channel

Expresiones analíticas de capacidad de sistemas MIMO-OSFBC

Orthogonal frequency-division multiplexing (OFDM) combined with orthogonal space-frequency block coding (OSFBC) has been shown to be a simple and efficient means to exploit the inherent spatial diversity of multiple-input-multipleoutput (MIMO) configurations in frequency-selective channels. In this paper we derive simple analytical closed-form expressions for the ergodic and outage capacity of OSFBC-OFDM systems assuming that the channel is unknown at the transmitter. The resulting expressions are simple functions of the spatial correlation matrices at the channel taps. They clearly reveal the dependence of the capacity on the channel and system parameters. Numerical results show the excellent accuracy of the derived expressions

Capacidad ergódica de sistemas MIMO basados en antenas con polarización dual

MIMO systems based on dual-polarized antennas at transmitter and receiver constitute an interesting alternative to conventional MIMO configurations. This paper analyzes the ergodic capacity of such systems in urban micro- and picocellular environments. The MIMO channel is modeled by using a site-specific ray-tracing propagation tool. This technique permits to analyze the impact of environmental parameters, like antennas location and orientation, on the system performance. Ergodic capacity estimations in a specific urban environment are presented

GCIMS: An R package for untargeted gas chromatography - Ion mobility spectrometry data processing

Gas-Chromatography coupled to Ion Mobility Spectrometry (GC-IMS) based metabolomics is an emerging technique for obtaining fast, reliable untargeted metabolic fingerprints of biofluids. The generated raw data is highly dimensional and complex, suffers from baseline problems, misalignments, long peak tails and strong non-linearities that must be corrected to extract chemically relevant features from samples. In this work, we present our GCIMS R package, which includes spectra loading, metadata handling, denoising, baseline correction, spectral and chromatographic alignment, peak detection, integration, and peak clustering to produce a peak table ready for multivariate data analysis. We discuss package design decisions, and, for illustration purposes, we show a case study of sex discrimination on the basis of the volatile compounds in urine samples. The GCIMS package provides a user-friendly workflow for non-code developers to process their raw data samples

Position control of a shape memory alloy actuator using a four-term bilinear PID controller

Shape memory alloy (SMA) actuators have a number of appealing features, such as their low weight or their high force-to-weight ratio, that make them a potential alternative to traditional actuation technologies in fields such as space applications, surgical devices or wearable robotics. In this paper, a type of bilinear controller consisting of a conventional PID controller cascaded with a bilinear compensator, known as BPID, is proposed. Bilinear controllers are a subset of nonlinear controllers, which is why the BPID may be a promising alternative to control the position of a SMA actuator. Nonlinear control techniques are commonly applied to control SMA actuators, because of their nonlinear behavior caused by thermal hysteresis. The BPID controller is simpler and easier to implement than other nonlinear control strategies, which makes it a very appealing candidate to control SMA actuators. The performance of the BPID controller has been compared with other two controllers, a conventional PID and a commuted feed-forward PIPD, controlling a real SMA actuator. To this end, a set of five tests has been defined, in which the controlled actuator must follow a series of position references. From these tests, the position and error of the actuator have been plotted, and a series of metrics has been computed to have quantitative measurements of the performance of the three controllers. It is shown that, in most of the experiments, the BPID has a better performance than the other two tested controllers, especially tracking step references. However, the power consumption is slightly higher when the actuator is controlled with this strategy, although-the difference is minimal. Also, the BPID imposes greater energy variations to the SMA actuator, which might affect its service life. Overall, the BPID controller has proved to be a viable alternative to control SMA actuators.The research leading to these results has received funding from the STAMAS (Smart technology for artificial muscle applications in space) project, funded by the European Union’s Seventh Framework Programme for Research (FP7) (grant number 312815), and from the RoboHealth (DPI2013-47944-C4-3-R) Spanish research project

Biología floral y polinización de Ipomoea murucoides Roem. & Schult. (Convolvulaceae) en Ixtapan del Oro, Estado de México (México)

En el presente estudio se describen algunas de las adaptacionesde las flores de Ipomoea murucoides con respecto a su interaccióncon los visitantes florales así como el sistema de reproducción se-xual en una Selva Baja Caducifolia de México. La antesis crepus-cular, el patrón en la producción de néctar y la concentración deazúcares, el pedicelo robusto y el color y tamaño de las flores soncongruentes con el síndrome floral de la quiropterofília. No obs-tante, se observó que además del murciélago Anoura geoffroyi, lasflores de I. murucoides también las visitaron durante el día colibrí-es (Colibri thalassinus, Eugenes fulgens y Heliomaster constantii),abejas carpinteras (Xylocopa guatemalensis y X. tenuata) y esca-rabajos (Cerambycidae). Los murciélagos, al ser los primeros visi-tantes de las flores, resultaron ser los polinizadores más importan-tes de I. murucoides, una especie alógama y, al parecer, autoin-compatible