El impacto de las capacidades dinámicas y la orientación al mercado sobre el rendimiento de las empresas: un estudio de caso de empresas consultoras de educación superior

[ENG] Dynamic capabilities (DC) and market orientation (MO) have been described as affecting firm performance, particularly in the case of fast-changing markets. They have been analysed for a wide range of firm sizes, but research on DC in the context of sole traders and micro enterprises is scarce. To begin filling this gap, this research focuses on the effects of DC and MO on firm performance in the case of sole traders, micro and small enterprises (MSEs), using higher education (HE) consulting as a case study. HE consulting was chosen as it is comprised of numerous sole traders and MSEs and it is subjected to significant and continual change. Using a survey completed by 60 MSEs based in the UK, Europe and North America, this research found that the sensing capability is a significant determinant of firm performance, alongside what this study defines as operational MO. Furthermore, operational MO was found to significantly moderate the relationship between the learning capability and firm performance. This work suggests that (i) research on DC should be extended to sole traders and MSEs; and (ii) the business literature is ripe for a growing body of applied work on DC going beyond their theoretical validation and looking to develop practical recommendations for firms in different industry sectors.[SPA] Muchos trabajos han descrito como las capacidades dinámicas (CD) y la orientación del mercado (OM) afectan al rendimiento de las empresas, en particular en el caso de mercados dinámicos. También, se han analizado en relación con una amplia gama de tamaños de empresas, pero las investigaciones sobre las CD en el contexto de los pequeños comercios y microempresas son escasas. Para empezar a llenar este vacío, esta investigación se centra en los efectos de las CD y la OM sobre el rendimiento de las empresas para el caso de comerciantes individuales y micro y pequeñas empresas (PYMEs), utilizando la consultoría de educación superior como estudio de caso. Se eligió la consultoría de educación superior porque está compuesta por numerosos comerciantes individuales y PYMEs y está sujeta a cambios significativos y continuos. Utilizando una encuesta completada por 60 PYMEs con base en el Reino Unido, Europa y América del Norte, esta investigación encontró que la búsqueda de oportunidades (sensing) es un determinante significativo del rendimiento de la empresa, junto con lo que este estudio define como OM operacional. Además, se encontró que el OM operacional modera significativamente la relación entre la capacidad de aprendizaje y el rendimiento de la empresa. Este trabajo sugiere que: i) la investigación sobre las CD debería ampliarse a los comerciantes individuales y a las PYMEs; y ii) la bibliografía empresarial está madura para un creciente volumen de trabajo aplicado sobre las CD que vaya más allá de su validación teórica y busque desarrollar recomendaciones prácticas para las empresas de diferentes sectores industriales

Stochastic generation of virtual air pores in granular materials

A computational method is described for the generation of virtual air pores with randomized features in granular materials. The method is based on the creation of a stack of two dimensional stochastically generated domains of packed virtual aggregate particles that are converted to three dimensions and made to intersect with one another. The three dimensional structure that is created is then sampled with an algorithm that detects the void space left between the intersected particles, which corresponds to the air void volume in real materials. This allows the generation of a map of the previously generated three dimensional model that can be used to analyse the topology of the void channels. The isotropy of the samples is here discussed and analysed. The air void size distribution in all the virtual samples generated in this study is described with the Weibull distribution and the goodness of fit is successfully evaluated with the Kolmogorov–Smirnov test. The specific surface of the virtual samples is also successfully compared to that of real samples. The results show that a stochastic approach to the generation of virtual granular materials based only on geometric principles is feasible and provides realistic results

Generation of virtual asphalt mixture porosity for computational modelling

A new algorithm is proposed for the computational generation of realistic asphalt mixture porosity for computational simulations. The algorithm starts by generating in a 2D domain a number of randomly positioned circular or elliptical elements that are meant to represent virtual asphalt aggregate particles. These elements are then grown by mimicking the biological mechanism called contact inhibition until a target air void content (AVC), chosen by the user, is met. In addition, multiple 2D domains can be converted to 3D and combined to generate a multi-layered realistic representation of the porosity present in asphalt mixtures. In this paper, the working mechanism of the algorithm is described and its efficiency is assessed. Moreover, the validity of the results is discussed, and virtual domains, in both 2 and 3 dimensions, are compared with real CT scans in order to show the efficacy of this approach. It was found that the virtual representations of the asphalt mixture porosity show realistic characteristics in terms of air void content and that the air void size distribution is consistent with that of real specimens

Energy harvesting pavements using air convection

Pavements are one of the most important components of modern civil infrastructure systems. Being constantly exposed to weather conditions, pavements may be subject to heating and cooling cycles, which vary as a function of the location and are proven to reduce the lifespan and reliability of our transport infrastructure. The most extreme effects of weather are generally seen in the form of overheating of the paving materials or freezing of the pavement surface. In this Thesis, natural convection of air is considered as a means to harvest heat from pavements during hot periods and to provide heat to them when the weather is cold. In the research presented, a buoyancy-driven air flow is allowed through metal pipes installed under an asphalt wearing course. The analysis of the phenomena at work is performed from an experimental, computational, and theoretical point of view. The main contribution to research provided by this Thesis it that the experiments performed show that a convection-powered air flow can be effectively used for the reduction or increase of pavement temperatures up to about �5°C. Moreover, the effects of variations in the design of energy harvesting pavements are quantified and discussed, proving that the installation of all pipes in a single row under the wearing course of a pavement is the overall best solution for the implementation of this technology. Finally, CFD simulations suggest that the air pores that are naturally present in asphalt mixtures are not suitable to allow the air flow required for convection-powered energy harvesting, due to both fluid-dynamic and practical reasons

Energy harvesting pavements using air convection

Pavements are one of the most important components of modern civil infrastructure systems. Being constantly exposed to weather conditions, pavements may be subject to heating and cooling cycles, which vary as a function of the location and are proven to reduce the lifespan and reliability of our transport infrastructure. The most extreme effects of weather are generally seen in the form of overheating of the paving materials or freezing of the pavement surface. In this Thesis, natural convection of air is considered as a means to harvest heat from pavements during hot periods and to provide heat to them when the weather is cold. In the research presented, a buoyancy-driven air flow is allowed through metal pipes installed under an asphalt wearing course. The analysis of the phenomena at work is performed from an experimental, computational, and theoretical point of view. The main contribution to research provided by this Thesis it that the experiments performed show that a convection-powered air flow can be effectively used for the reduction or increase of pavement temperatures up to about �5°C. Moreover, the effects of variations in the design of energy harvesting pavements are quantified and discussed, proving that the installation of all pipes in a single row under the wearing course of a pavement is the overall best solution for the implementation of this technology. Finally, CFD simulations suggest that the air pores that are naturally present in asphalt mixtures are not suitable to allow the air flow required for convection-powered energy harvesting, due to both fluid-dynamic and practical reasons

Training Future Engineers to Be Ghostbusters: Hunting for the Spectral Environmental Radioactivity

Although environmental radioactivity is all around us, the collective public imagination often associates a negative feeling to this natural phenomenon. To increase the familiarity with this phenomenon we have designed, implemented, and tested an interdisciplinary educational activity for pre-collegiate students in which nuclear engineering and computer science are ancillary to the comprehension of basic physics concepts. Teaching and training experiences are performed by using a 4" x 4" NaI(Tl) detector for in-situ and laboratory {\gamma}-ray spectroscopy measurements. Students are asked to directly assemble the experimental setup and to manage the data-taking with a dedicated Android app, which exploits a client-server system that is based on the Bluetooth communication protocol. The acquired {\gamma}-ray spectra and the experimental results are analyzed using a multiple-platform software environment and they are finally shared on an open access Web-GIS service. These all-round activities combining theoretical background, hands-on setup operations, data analysis, and critical synthesis of the results were demonstrated to be effective in increasing students' awareness in quantitatively investigating environmental radioactivity. Supporting information to the basic physics concepts provided in this article can be found at http://www.fe.infn.it/radioactivity/educational

Mesh Fixation Methods in Groin Hernia Surgery

No unanimous consent has been reached by surgeons in terms of a method for mesh fixation in laparoscopic and open surgery for inguinal hernia repair. Many different methods of fixation are available, and the choice of which one to use is still based on surgeons’ preferences. At present, tissue glues, sutures, and laparoscopic tacks are the most common fixating methods. In open technique, sutures have been the method of choice for their reduced costs and surgeons’ habits. Nevertheless, tissue glues have been demonstrated to be effective and safe. Similarly, tacks can be considered the most common means of fixation in laparoscopic hernia repair, but they are connected to a higher risk of complication and morbidity. In this chapter, we present these types of mesh fixation, their characteristics and potential risks, and advantages of their use

Pavement temperature mitigation by the means of geothermally and solar heated air

In this article, a novel method to mitigate pavement temperatures by the means of air convection is presented. The technique introduced here is based on a new type of experimental setup called a ground source heat simulator, which is able to feed air at a controlled temperature to a set of pipes embedded under a test pavement surface. The air at the chosen temperature can flow through the designed system by natural convection. The air heated by the simulated geothermal source can mitigate the pavement temperature in winter and summer conditions in order to avoid freezing and overheating of paving surfaces in an urban environment. In particular, during winter the geothermal air warms up the pavement, while during summer the pavement is cooled down. Laboratory tests of the ground source heat simulator allowed the collection of a high amount of data, which is here analysed statistically and computationally. This article shows that the use of geothermal energy to preheat the inlet air in pavements where an array of pipes is installed can provide a measurable contribution for the mitigation of pavement temperatures in both winter and summer conditions. Furthermore, the experimental data gathered successfully proved the effectiveness of computational simulations for the study of buoyancy powered air flow through channels buried under pavements and increased the understanding of the physical phenomena happening in the system under analysis. Finally, preliminary testing in the environment showed that the concept is effective and works as expected

The DprE1 enzyme, one of the most vulnerable targets of Mycobacterium tuberculosis

n/