What are the organizational conditions for learning and knowledge management? Evidence from large spanish firms

The phenomena of globalization and the intensification of change mean that firms increasingly re­quire an internal climate that fosters the genesis and application of new knowledge. If the firm's objective is to achieve continuous learning, organizational variables and managerial purpose are essential for access to superior knowledge assets. This study takes an in-depth look at the relationship between a political phenomenon (knowledge management) and a natural one (organizational learning) within a particular or­ganizational framework. The aim is to obtain evidence of the effect of organizational variables on learning and knowledge from the perspective of large Spanish firms

A new controller for the inverted pendulum on a cart

This paper presents a complete solution to the problem of swinging-up and stabilization of the inverted pendulum on a cart, with a single control law. The resulting law has two parts: first, an energy-shaping law is able to swing and maintain the pendulum up. Then, the second part introduces additional control to stop the cart and it is based on forwarding control with bounded input. The resulting control law is the sum of both parts and does not commute between different laws although there exist switches inside the controller.MEC-FEDER DPI2006-0733

Stabilization of oscillations through backstepping in high-dimensional systems

This paper introduces a method for obtaining stable and robust self-sustained oscillations in a class of single input nonlinear systems of dimension n ≥ 2. The oscillations are associated to a limit cycle that is produced in a second-order subsystem by means of an appropriate feedback law. Then, the controller is extended to the full system by a backstepping procedure. It is shown that the closed-loop system turns out to be generalized Hamiltonian and that the limit cycle can be thought as born in a Hopf bifurcation after moving a parameter.Ministerio de Ciencia e Innovación (España

A family of smooth controllers for swinging up a pendulum

Es el primer envío que hago. Le agradeceré si me confirma que es todo correcto, especialmente el cumplimiento de los derechos de propiedad de la editorial. Mi email es [email protected] paper presents a new family of controllers for swinging up a pendulum. The swinging up of the pendulum is derived from physical arguments based on two ideas: shaping the Hamiltonian for a system without damping; and providing damping or energy pumping in relevant regions of the state space. A family of simple smooth controllers without switches with nice properties is obtained. The main result is that all solutions that do not start at a zero Lebesgue measure set converge to the upright position for a wide range of the parameters in the control law. Thus, the swing-up and the stabilization problems are simultaneously solved with a single, smooth law. The properties of the solution can be modified by the parameters in the control law. Control signal saturation can also be taken into account using the Hamiltonian approach.MCyT-FEDER DPI2006-0733

Asymptotic rejection of sinusoidal disturbances based voltage balance control in back-to-back power converters

This paper addresses the imbalance problem of the dc-link capacitor voltages in the three-level diode-clamped back-to-back power converter. In order to cope with it, a mathematical analysis of the capacitor voltage difference dynamics, based on a continuous model of the converter, is first carried out. It leads to an approximated model which contains explicitly several sinusoidal functions of time. In view of this result, the voltage imbalance phenomenon can be addressed as an output regulation problem, considering the sinusoidal functions as exogenous disturbances. Thus, a novel approach to deal with the mentioned problem in the back- to-back converter is presented. Then, the particular features of the disturbances are used to design several controllers. They all follow an asymptotic disturbance rejection approach. In this way, the estimations of the disturbances are used to apply a control law that cancels them while regulating the capacitor voltage balance as well. Finally, the performance of the proposed control laws is evaluated, presenting the simulation results obtained when the different controllers are implemented.MICINN-FEDER DPI2009-0966

Efecto agudo del estiramiento activo sobre la fuerza y potencia de la flexión y extensión de rodilla Acute effect of active stretching on knee flexion and extension strength and power output

Aim To analyze the acute effect of a short duration active-static stretching protocol on maximal isokinetic strength and power output during concentric and eccentric flexion and extension knee movements in recreational athletes. Method A total of 27 males and 25 females completed three measurement sessions, an initial session of familiarization and two experimental session (control and active stretching in randomized order) with 72–96 hours interval among consecutive sessions. The active stretching protocol consisted in 5 different unilateral exercises designed to stretch the major lower limb muscle groups. Each stretching exercise was performed twice, holding the position during 30s (2 × 30s), with a rest-interval among series, contra-lateral leg and /or exercises of 20s. In the control session no stretching exercises were performed. Immediately after performed both treatments (control and stretching), the isokinetic indexes of peak torque (PT) and average power (AP) were tested during concentric and eccentric flexion and extension knee movements. Results The ANOVA analysis carried out revealed no significant interaction effect between testing sessions (control and stretching) for knee flexion and knee extension peak torque and mean power in both concentric and eccentric muscle contractions. Conclusions Short (2 × 30s per muscle group) pre-exercise active-static lower-limb stretching routine did not elicit stretching-induce reductions in knee flexor and knee extensor isokinetic concentric and eccentric strength

Active Stretching and Eccentric Length-Tension Relationship of Hamstring Muscles

The purpose of this study was to investigate the acute effect of an active lower limb stretching routine with a sports-related training load on the hamstring eccentric length-tension relationship. 49 recreational sportsmen completed three assessment sessions, an initial familiarization session and two experimental sessions (control and stretching in random order). Immediately after the interventions (stretching or control), eccentric isokinetic peak torque, maximum force angle and total work were measured in prone position. If the alteration of the eccentric length-tension relationship could be used as a primary risk factor of hamstring muscle strains, the findings of the present study tentatively suggest that static stretching would not be able to alter the relative risk of hamstring muscles

Active Stretching and Eccentric Length-Tension Relationship of Hamstring Muscles

The purpose of this study was to investigate the acute effect of an active lower limb stretching routine with a sports-related training load on the hamstring eccentric length-tension relationship. 49 recreational sportsmen completed three assessment sessions, an initial familiarization session and two experimental sessions (control and stretching in random order). Immediately after the interventions (stretching or control), eccentric isokinetic peak torque, maximum force angle and total work were measured in prone position. If the alteration of the eccentric length-tension relationship could be used as a primary risk factor of hamstring muscle strains, the findings of the present study tentatively suggest that static stretching would not be able to alter the relative risk of hamstring muscles

Predicting mobile apps spread: An epidemiological random network modeling approach

[EN] The mobile applications business is a really big market, growing constantly. In app marketing, a key issue is to predict future app installations. The influence of the peers seems to be very relevant when downloading apps. Therefore, the study of the evolution of mobile apps spread may be approached using a proper network model that considers the influence of peers. Influence of peers and other social contagions have been successfully described using models of epidemiological type. Hence, in this paper we propose an epidemiological random network model with realistic parameters to predict the evolution of downloads of apps. With this model, we are able to predict the behavior of an app in the market in the short term looking at its evolution in the early days of its launch. The numerical results provided by the proposed network are compared with data from real apps. This comparison shows that predictions improve as the model is fed back. Marketing researchers and strategy business managers can benefit from the proposed model since it can be helpful to predict app behavior over the time anticipating the spread of an appAlegre-Sanahuja, J.; Cortés, J.; Villanueva Micó, RJ.; Santonja, F. (2017). Predicting mobile apps spread: An epidemiological random network modeling approach. Transactions of the Society for Computer Simulation. 94(2):123-130. https://doi.org/10.1177/0037549717712600S12313094