Tourist accommodation pricing through peer-to-peer platform: evidence from Seville (Spain)

The expansion of holiday rentals’ worldwide makes it relevant to confirm what are the determinants of these accommodations’ daily rates. This research aims to compare two models on estimating holiday rentals’ daily rate through variables that influence it; using artificial neural networks and hedonic pricing method, with the same cross-sectional dataset and variables with data obtained from Booking.com listings from Seville (Spain), a ‘cultural tourism’ large European city. Artificial neural networks estimations adapt better than the hedonic pricing method due to non-linear relations involved, although hedonic estimators have a clearer economic interpretation. Variables related to size, location and amenities appear as the most relevant in the models, including also seasonal and special events factors. The models presented, not only help to clarify these variables but also allow estimating a rental price congruent with the characteristics of the dwelling and season, being useful as an objective valuation method for the main agents of the accommodation sector: Owners, clients and peer-to-peer platforms. This study wants to highlight the convenience of using Booking.com listings as the main data source, as two variables presented as relevant for the models (size and location) are not available in other peer-to-peer platforms like Airbnb

The new challenges of the manufacturing industry applying the norm ISO 45001:2018

The present work reflects the impact that the manufacturing industries must solve in the application of the ISO 45001: 2018 Standard on Occupational Health and Safety Management Systems. In such, a globalized market where human and material assets must be preserved for the survival of organizations, management systems based on continuous improvement play an important role in ensuring compliance with applicable legal requirements, risk management and the opportunities, as well as the achievement of the best working conditions. The manufacturing industry has not been alien to this evolution; the nature of the risks present in the different industries, the operations carried out, the machinery, the use of work teams and their processes make this sector a priority and strategic sector that should be at the forefront of new technologies and rules. The implementation of the ISO 45001: 2018 standard in the manufacturing industry is a challenge for the implementation of high-level management systems that guarantee a healthy and safe environment for workers and a strategic and operational decision from the business point of view based on improving the performance of health and safety at work and increasing competitiveness in an increasingly demanding market.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

A comparative study of image processing thresholding algorithms on residual oxide scale detection in stainless steel production lines

The present work is intended for residual oxide scale detection and classification through the application of image processing techniques. This is a defect that can remain in the surface of stainless steel coils after an incomplete pickling process in a production line. From a previous detailed study over reflectance of residual oxide defect, we present a comparative study of algorithms for image segmentation based on thresholding methods. In particular, two computational models based on multi-linear regression and neural networks will be proposed. A system based on conventional area camera with a special lighting was installed and fully integrated in an annealing and pickling line for model testing purposes. Finally, model approaches will be compared and evaluated their performance..Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Numerical Integration of Lattice Systems with a Lyapunov Function

In this contribution we implement and assess numerical methods for gradient systems, i.e. dynamical systems that possess a Lyapunov function, and consequently are stable. In particular, we claim that discrete gradient methods are well suited to so-called lattice systems, i.e. systems of ordinary differential equations that can reach high dimensionality. For these systems, reproducing the stable qualitative behaviour is more important than achieving an overly accurate quantitative approximation. The presented results show that discrete gradient methods outperform conventional Runge-Kutta methods, since these latter algorithms destroy the stability of the original system.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Geometric integration methods of high order for gradient systems

We propose the higher order extension of numerical methods that preserve the energy-diminishing feature of a system with Lyapunov function.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Numerical Methods That Preserve a Lyapunov Function for Ordinary Differential Equations

The paper studies numerical methods that preserve a Lyapunov function of a dynamical system, i.e., numerical approximations whose energy decreases, just like in the original differential equation. With this aim, a discrete gradient method is implemented for the numerical integration of a system of ordinary differential equations. In principle, this procedure yields first-order methods, but the analysis paves the way for the design of higher-order methods. As a case in point, the proposed method is applied to the Duffing equation without external forcing, considering that, in this case, preserving the Lyapunov function is more important than the accuracy of particular trajectories. Results are validated by means of numerical experiments, where the discrete gradient method is compared to standard Runge–Kutta methods. As predicted by the theory, discrete gradient methods preserve the Lyapunov function, whereas conventional methods fail to do so, since either periodic solutions appear or the energy does not decrease. Moreover, the discrete gradient method outperforms conventional schemes when these do preserve the Lyapunov function, in terms of computational cost; thus, the proposed method is promising.This work has been partially supported by Project PID2020-116898RB-I00 from the Ministerio de Ciencia e Innovación of Spain and Project UMA20-FEDERJA-045 from the Programa Operativo FEDER de Andalucía. Partial funding for open access charge: Universidad de Málag

Caracterización técnico-didáctica de los procesos deportivos en los clubes de fútbol de Pereira

La presente investigación se concentró en la determinar las características técnico-didácticas de los procesos deportivos adelantados en los clubes deportivos de fútbol en el municipio de Pereira, de manera específica con los que registraban vigencia activa actualizada del aval o reconocimiento deportivo otorgado por la Liga Risaraldense de Futbol, con un tiempo no inferior a tres meses al momento de la iniciación del estudio. Como criterio de muestreo se utilizó el censo no probabilístico e intencionado. El proceso metodológico del estudio se adelantó con un diseño no-experimental de tipo transaccional (transversal o sincrónico) en el nivel exploratorio-descriptivo, a través de una encuesta semi-estructurada fundamentada en preguntas cerradas de selección múltiple acerca de aspectos considerados vitales para el funcionamiento técnico-didáctico de los clubes y adelantados sobre prácticas deportivas formativas o competitivas. Los resultados del estudio arrojaron bajos niveles de formación en los técnicos donde prevalece la formación académica tecnológica deportiva, circunstancia que plantea la necesidad de cualificación en la formación del entrenador deportivo, y la adquisición de competencias en este dominio, especialmente en un momento como el actual en el que existe una gran expansión de la práctica deportiva en diferentes contextos y niveles de práctica que exige entrenadores cualificados para el ejercicio de esta función. Esta situación decrece al establecer que una gran mayoría de los entrenadores no cuenta con un diario de campo y las tareas técnicas desplegadas se caracterizan por un carácter repetitivo, mecánico de ejercicios sin secuencia metodológico coherente, mientras que las tareas motrices no incorporan ejercicios, que cumpliendo principios pedagógicos fundamentales, le permitan al niño o joven no solo la familiarización y la asimilación de las habilidades con métodos de enseñanza acordes a su nivel de madurez biológica y motora.The present investigation focused on determining the technical and educational characteristics of the processes developed in sports soccer sports clubs in the city of Pereira, specifically with the active force that recorded date of the guarantee or recognition granted by the League sports Risaralda Soccer, with not less than three months at the time of study initiation. As a criterion sampling was used census and intentional non-probabilistic. The methodology of the study went forward with a non-experimental, transactional (cross or synchronous) in the exploratory-descriptive level, through a survey based on semi-structured multiple choice closed questions on issues considered vital to the technical operation of the clubs training and advanced training practice or competitive sports. The results of the study showed low levels of technical training in the academic education where technology prevails sport, a fact which raises the need for qualifications in sports coaching training and skills development in this area, especially at a time like the present where there is a great expansion of the sport in different contexts and levels of practice that requires qualified coaches for the exercise of this function. This decreases to establish that a vast majority of coaches do not have a field day and deployed technical tasks are characterized by repetitive, mechanical exercise without consistent methodological sequence, while the motor tasks do not incorporate exercises that meet fundamental pedagogical principles, to enable the child or young person not only familiarization and assimilation of skills teaching methods appropriate to their level of biological maturity and motor

La importància de les eines computacionals en el disseny d'enzims d'interès industrial

El camp del disseny d'enzims té com a principal objectiu el desenvolupament d'enzims modificats per tal d'accelerar noves reaccions o d'acceptar substrats no naturals. Tot i els avenços en el camp, encara no s'ha assolit el disseny rutinari d'enzims. L'evolució dirigida (DE) és una de les estratègies més poderoses que existeixen, però el seu alt cost i el fet de ser una estratègia no racional en limita l'aplicació. La comprensió de com l'evolució dirigida és capaç d'obtenir variants altament actives és crucial per al futur desenvolupament de protocols computacionals robusts capaços de predir amb precisió quins canvis d'aminoàcids són necessaris per a tenir alta activitat enzimàtica. En aquest treball, es demostra la importància dels mètodes computacionals, en particular, els basats en simulacions de dinàmica molecular, per a elucidar l'efecte de mutacions al centre actiu i a posicions llunyanes en l'activitat i selectivitat enzimàtica.The enzyme design field pursues the development of new modified enzyme variants to target new synthetically useful reactions and/or substrates. Although many advances have been made, the routine design of enzymes has not yet been achieved. Directed evolution (DE) is one of the most powerful strategies that exist to that end but its high cost and the fact that it is not rational limit its application. The understanding of how DE is able to provide highly active variants is crucial to the future development of robust computational protocols capable of accurately predicting which amino acid changes are required for high enzymatic activity. In this paper, we show the important role of computational methods, in particular molecular dynamics (MD) simulations, for elucidating the effect of distal and active site mutations that lead to enhanced enzymatic activity and selectivity