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This paper is focused on the methodological aspects of the numerical study of stress intensity factor (SIF) evolution through thickness. The work evaluates the modelling of an Al-alloy 2024-T351 CT specimen under mode I nominal loading in fracture. No plastic wake effect is introduced to separate the influence of plasticity-induced crack closure near the surface. Numerical models have shown the complexity 3-D behaviour in the vicinity of the crack front and finite element methods (FEM) are widely used in these problems with interesting results. However, there is a lack of literature support in many simplifying assumptions. In previous studies, authors have analysed some issues as the evolution of the plastic zone, the crack closure stress or the SIF. The current work attempts to describe and justify the key aspects of the methodology developed to address these problems by the FEM. A huge effort has been made to study main parameters involved and their influence in the results, especially in order to properly capture the SIF distribution along the thickness. Recommendations about mesh density are provided, and the main procedures to obtain K are discussed. more...

191 páginas Al hablar de inclusión, se piensa en todo el proceso social y académico que esto acarrea y como implementarlo de la mejor manera. En el proceso social los actores que intervienen en la educación, acatan, algunos con displicencia, la normatividad que rige sobre la inclusión, pero es en el proceso académico donde surge las inquietudes sobre que estrategias pedagógicas y evaluativas son más aptas para estudiantes en condición de discapacidad intelectual o dificultad de aprendizaje, preocupándose aún más, cuando se tratan de estrategias para la enseñanza de la lectura, escritura y oralidad del ciclo I, generando en algunos docentes el interés y en otros levantando barreras. El propósito de esta investigación es recoger la información de estudiantes, docentes, padres de familia y expertos frente al tema para a partir de estas, poder plantear una propuesta de estrategias pedagógicas y evaluativas desde la perspectiva diferencial que responda a las necesidades de todos los involucrados y que incluya la innovación utilizando las secuencias didácticas como insumo enriquecedor de los procesos pedagógicos. more...

Informe resumen de la evaluación del Proyecto de Electrificación Rural en la V sección de la Provincia de Pacajes (La Paz) en Bolivia, durante julio y agosto de 1998.

D. Camas, F.V. Antunes, B. Moreno, A. Gonzalez-Herrera, Numerical analysis of the influence of the last cycle scheme on plasticity induced crack closure, Book of Abstracts of the 3rd International Conference on Structural Integrity, pp. 185. Plasticity induced crack closure is considered the main mechanism related to the premature contact of the crack flanks when a crack grows under cyclic loadings. This phenomenon has been studied numerically since the early 70s, when some researchers approached to metal fatigue problems by means of the finite element analysis. The numerical analysis requires the development of a plastic wake. How this plastic wake is developed has influence on the crack closure results and a great impact on the computational cost. When running a finite element analysis, it is not possible to consider all the loading cycles involved in an experimental test. The numerical effort is not acceptable. Therefore, in this work, the crack growth scheme is analyzed. In particular, the influence of the number of loading cycles after releasing the last set of nodes on plasticity induced crack closure results is studied. A CT aluminum specimen has been modelled three-dimensionally and several simulations have been run to evaluate the influence of the loading cycles after releasing the last set of nodes. The numerical analysis is made in terms of crack closure and opening values. Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. more...

se presentan los resultados obtenidos en el desarrollo de prácticas piloto sobre respuestas dinámicas de estructuras encaminadas a la mejora de la asimilación de conceptos dinámicos a lo largo del itinerario de estudios de grados relacionados con la ingeniería industrial. Se trata de experiencias que se engloban dentro de un proyecto de innovación docente de carácter bianual. Los resultados refuerzan nuestra idea de la necesidad de implementar estas actividades de forma escalonada en distintas asignaturas de nuestro departamento. Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. more...

Informe resumen del Programa de Electrificación Rural en el altiplano boliviano realizado con la participación de IPADE y AECID (1990 – 1998), realizado por el autor en el marco de la evaluación y estudio de dicho programa y los proyectos que lo desarrollan. more...

Informe resumen de las visitas de evaluación al Proyecto de Electrificación Rural en la V sección de la Provincia de Pacajes (La Paz) en Bolivia, durante julio y agosto de 1998, realizadas por el autor en el marco de la evaluación y estudio del Programa de Electrificación Rural en el altiplano boliviano realizado con la participación de IPADE y AECID (1990 – 1998) more...

This project is focused on designing a drone capable of inspecting the interior of primary air conditioning ducts autonomously. The study is divided into five chapters. The first chapter deals with the regulations applied in air duct reviews at the Spanish state level. The implications of the activity of a drone in these operations are also sought in the RPA regulations. And finally, it is explained in detail how these duct inspection operations are currently carried out and how they could be carried out with a drone. The second chapter focuses on the market study, in a first search on the devices currently conducting duct inspections, which are mobile robots. Secondly, a drone market study is carried out that can develop similar or equal applications to the ones we are looking for. And thirdly, a study of potential customers at the level of the Spanish state that may be interested in acquiring the designed drone is carried out. Finally, an assessment is made of the data found that will serve as a basis to start designing the drone. In the third chapter, the points obtained from the previous section are developed by dividing the drone into the different components that it carries. Studying and analyzing each of them separately and choosing in the current market the component that best suits the design and the desired characteristics. In the fourth chapter, it is intended to develop the prototype of the drone designed in different phases. In this project it is possible to reach phase 2, which is the objective set, but it is left open so that the drone designed can be developed exactly, with the applications and features designed. Finally, in the fifth chapter the results obtained in general of the project are briefly analyzed, including the tests carried out in the different phases of the prototype, and the viability of the project is determined. Este proyecto estáfocalizado en diseñar un drone capaz de inspeccionar el interior de conductos de climatización de aire primariode forma autónoma. El estudio realizado se divide en cinco capítulos.El primer capítulotrata sobre la normativa aplicada en las revisiones de los conductos de aire a nivel del estado español. Tambiénse busca en la normativa de los RPA, las implicaciones de la actividad de un drone en estas operaciones. Y por último, se explica detalladamente como se llevan actualmente estas operaciones de inspección de conductos y como se podrían llevar a cabo con un drone.El segundo capítuloestáfocalizado en el estudio de mercado, en una primera búsqueda sobre los dispositivos que realizan actualmente las inspecciones de conductos, que son los robots móviles. En segundo lugar se realiza un estudio de mercado de drones que puedan desarrollar aplicaciones similares o iguales a las que estamos buscando. Y en tercer lugar se realiza un estudio de los clientes potenciales a nivel del estado español que les pueda interesar la adquisición deldrone diseñado. Por último, se realiza una valoración de los datos encontrados que servirán como base para empezar a diseñar eldrone.En el tercer capítulo, se desarrollan los puntos obtenidos del apartado anterior dividiendo el drone en los diferentes componentes que lleva consigo. Estudiando y analizando por separado cada uno de ellos y escogiendo en el mercado actual el componente quemejorse adapta al diseñoy las características deseadas.En el cuarto capítulo, se pretende desarrollar el prototipo del drone diseñado en fases diferentes. En este proyecto se logra llegar hasta la fase 2,que es el objetivo marcado, pero se deja abierto para que se pueda llegar a desarrollar exactamente el drone diseñado, con las aplicaciones y características ideadas.Finalmente, en el quinto capítulobrevemente se analizan los resultados obtenidos en general del proyecto, incluido las pruebas realizadas en lasdiferentes fases del prototipo, y se determina la viabilidad del proyecto. more...

Daniel Camas, Fernando Antunes, Pablo Lopez-Crespo, Antonio Gonzalez-Herrera, 3D Numerical Study of the Transient Behaviour on Plasticity Induced Crack Closure, Abstract Booklet of the MSMF9, Edited by Pavel Sandera, Brno University of Technology, 2019, pp. 136. The numerical analysis of the plasticity induced crack closure requires the development of the plastic wake. Transient behaviour is observed when the crack starts to grow. The plastic wake length has an influence on the crack closure results and a great impact on the computational cost. Previous works have analysed the influence of this parameter considering bi-dimensional specimens in either plane strain or plane stress conditions. Lately, some three-dimensional models have appeared in order to analyse the crack closure phenomenon. The main scope of this study is to quantify and comprehend the minimum length required to stabilise the crack opening and closure values considering a three-dimensional model. On this purpose, a CT aluminium specimen has been modelled three-dimensionally and several calculations have been made in order to evaluate the influence of the simulated plastic wake. The numerical analysis is made in terms of crack closure and opening values. Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech more...

A circular economy is a current tenet that must be implemented in the field of construction. That would imply the study of the possibilities of the use of waste generated, for obtaining materials the used in construction as replacements for the raw material used. One of these possibilities is the substitution of the cement by slag, which contributes to the reduction of cement consumption, decreasing CO2 emissions, while solving a waste management problem. In the present paper, different types of concrete made by cement substitution with different type of slags have been studied in order to evaluate the properties of these materials. Cement is replaced by slag from different steel mills, both blast furnace and ladle furnace slag. The percentages of slag substitution by cement are 30%, 40% and 50% by weight. Mechanical, physical and environmental properties have been evaluated. Compressive and flexural strength have been analysed as the main mechanical properties. As far as physical properties go, density and porosity tests were be reported and analysed, and from an environmental point of view, a leachate study was performed. It has been found that some kinds of slag (blast furnace slag) are very suitable as substitutes for cement, providing properties above those of the reference concrete, while other types (ladle furnace slag) could be valid for non-structural applications, contributing in both cases to a circular economy. Agência financiadora Center of Industrial Technological Development (CDTI) of the Ministry of Economy and Competitiveness IDI-20160509 info:eu-repo/semantics/publishedVersion more...

El tema que se va a desarrollar es el Principio de los Trabajos Virtuales así como sus aplicaciones en su formulación para estructuras de nudos articulados con cargas en los nudos. Se trata de un tema de gran trascendencia no ya sólo por la utilidad que presenta en sí, sino por la cantidad de aplicaciones que tiene en todo el campo de la mecánica de medios continuos en general y la teoría de estructuras en particular. more...

Informe resumen de las visitas de evaluación al Proyecto de Electrificación Rural en la III sección de la Provincia de Pacajes (La Paz) en Bolivia, durante agosto de 1998, realizadas por el autor en el marco de la evaluación y estudio del Programa de Electrificación Rural en el altiplano boliviano realizado con la participación de IPADE y AECID (1990 – 1998) more...

El presente documento recoge de una manera general la información obtenida durante la visita realizada a la V Sección de la Provincia de Pacajes (La Paz), en septiembre de 2009, por los autores para la valoración y estudio del proyecto de electrificación rural ejecutado por IPADE y AECI - OTC Bolivia desde 1996 a 1998. more...

Informe completo de la evaluación del Proyecto de Electrificación Rural en la V sección de la Provincia de Pacajes (La Paz) en Bolivia, durante julio y agosto de 1998.

In recent years, multi-agent path planning is a topic of interest to robotics. This paper studies the problem of multirobot path planning to search for lost people in a natural environment; known as WiSAR (Wilderness Search and Rescue). WiSAR is an optimization problem which requires: i) a fast and effective coverage of the area, and ii) to minimize the time, and distance traveled for finding the target. Heuristic algorithms find approximate solutions at an acceptable complexity both in time and space. This paper presents new adaptations to the Bacterial Foraging Optimization Algorithm (BFOA) that allow: 1) Semi-guided navigation and 2) Taking decisions based on a probabilistic model that represent the dynamic environment. The algorithm was simulated in the Matlab platform by using a 2-D plane. Experimental results show that the proposed technique reduces 60.7% of the time and 70.6 % of the distance traveled (in average) with respect to the Grid Search technique when five agents are used in a search of a child in outdoors. Results show that this reduction can be much greater when fewer agents are deployed or the person moves at a higher rate. more...

In this paper we will report on the status of the instrumentation project for the European Southern Observatory's Extremely Large Telescope (ELT). Three instruments are in the construction phase: HARMONI, MICADO and METIS. The multi-conjugate adaptive optics system for MICADO, MAORY, is also under development. Preliminary Design Reviews of all of these systems are planned to be completed by mid-2019. The construction of a laser tomographic module for HARMONI is part of "Phase 2" of the ELT: the design has been advanced to Preliminary Design level in order to define the interface to the HARMONI spectrograph. Preparations for the next instruments have also been proceeding in parallel with the development of these instruments. Conceptual design studies for the multi-object spectrograph MOSAIC, and for the high resolution spectrograph HIRES have been completed and reviewed. We present the current design of each of these instruments and will summarise the work ongoing at ESO related to their development. more...

Concrete consumption greatly exceeds the use of any other material in engineering. This is due to its good properties as construction material and the availability of its components. Nevertheless, the present worldwide construction increase and the high-energy consumption for cement production means a high environmental impact. On the other hand, one of the main problem in iron and steel industry is waste generation and by-products that must be properly processed or reused to promote the environmental sustainability. One of these by-products are blast furnace slag. Cement substitution by slag strategy achieves two goals, raw materials consumption reduction and waste management. In the present work, four different concrete mixtures are evaluated. 25% cement is substituted by different blast furnace slag. Tests are made to evaluate the advantages and drawbacks of each mixture. Depending on the origin, characteristics and treatment of the slag, concrete properties change. Certain mixtures provide proper concrete properties. Stainless steel slag produces a fluent mortar that reduces the water consumption whit a slight mechanical strength loss. Mixture with electric arc slag furnace properties are better to the reference concrete (without slag) when slag is treated similarly to the cement. more...

Industries integration is a promising source of sustainability. Sugar cane industry must redesign the production processes, including new emerging technologies, in order to retain the status of competitive industry. The integration is a complex process accomplish by engineers where de main problems are alternative generation and alternative comparing. Engineers must execute several subtasks like: factory retrofit, macro-localization, dynamic indicators computing and so on. Processes engineer is complex, so, a good computation support is needed. In this work we state that existent tools are not enough to accomplish this supporting. In this paper we analyze industrial integration like a process, composite by several decisions, executed by engineers. Useful computational technologies and methods are presented. These methods are our bricks for a tool supporting every single process engineer task. Some of the presented methods had been used previously but need to be adapted to this industry. Our approach is not only to integrate existent tools o creating new tools but automating most decision making. Finally, we show a typical case of sugar cane industry integration. In this case several modifications are needed in order to be competitive; engineers must select raw aterials and technologies to use in the production of furfural, ethanol and citric acid. The technologies involved in this case can use sugar molasses, bagasse and sugar cane straw as raw material. The optimization sults for this problem show the advantages of integrating several raw materials sources. more...

The classical picture of middle ear (ME) transmission has the tympanic membrane (TM) as a piston and the ME cavity as a vacuum. In reality, the TM moves in a complex multiphasic pattern and substantial pressure is radiated into the ME cavity by the motion of the TM. This study explores ME transmission with a simple model, using a tube terminated with a plastic membrane. Membrane motion was measured with a laser interferometer and pressure on both sides of the membrane with micro-sensors that could be positioned close to the membrane without disturbance. A finite element model of the system explored the experimental results. Both experimental and theoretical results show resonances that are in some cases primarily acoustical or mechanical and sometimes produced by coupled acousto-mechanics. The largest membrane motions were a result of the membrane's mechanical resonances. At these resonant frequencies, sound transmission through the system was larger with the membrane in place than it was when the membrane was absent. more...

Cancer cells use glucose and glutamine to facilitate cell growth and proliferation, a process coined "metabolic reprograming" - an emerging hallmark of cancer. Inside the cell, these nutrients synergize to produce metabolic building blocks, such as nucleic acids, lipids and proteins, as well as energy (ATP), glutathione and reducing equivalents (NADPH), required for survival, growth and proliferation. Intense research aimed at understanding the underlying cause of the metabolic rewiring has revealed that established oncogenes and tumor suppressors involved in signaling alter cellular metabolism to contribute to the transition from a normal quiescent cell to a rapidly proliferating cancer cell. Likewise, bona fide metabolic sensors are emerging as regulators of tumorigenesis. This review will focus on one such family of sensors, sirtuins, which utilize NAD(+) as a cofactor to catalyze deacetylation, deacylation and ADP-ribosylation of their protein substrates. In this review, we will enumerate how cancer cell metabolism is different from a normal quiescent cell and highlight the emerging role of mitochondrial sirtuin signaling in the regulation of tumor metabolism. more...

Recent studies have allowed us to identify a narrow region of the thickness of the crack front in fracture problems that presents interesting characteristics for the numerical-experimental correlation. Taking the three-dimensional distribution of the stress intensity factor (K) as a reference, we observe how it remains invariant and independent of the main factors influencing this type of analysis. This article presents a summary of how to identify this point through the numerical simulation of the problem and its relationship with parameters such as thickness, load level or angle of curvature. The simulations are carried out with the ANSYS software in an aluminium CT specimen subjected to a fracture loading process in mode I. Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. more...

Since long time, fatigue crack closure has been studied by means of finite element models. Initially by bi-dimensional models and recently, due to the higher computational capabilities, the use of three-dimensional models has been extended, providing a wider comprehension of the problem. Starting with the methodology used for 2D cases, a specific methodology for 3D models has been developed. Key parameters affecting the model have been analyzed and recommendations have been established. The numerical accuracy is evaluated in terms of crack closure and opening values. They main issues studied are the material behaviour, the loading cycles and crack growth scheme, the contact simulation, the meshing and the element size at the crack tip and along the thickness, the plastic wake computed and the opening and closure definition considered. This paper summarises the main learning and recommendations from the latest numerical modelling experience of the authors. Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. more...

Background: Cervical cancer (CeCa) is the second most common cancer in women in developing countries, and human papilloma virus (HPV) is the primary etiological factor. Aberrant expression of HOX transcription factors has been observed in several types of cancer. To date, however, no reports exist on the expression of HOXB2 and HOXB13 proteins during neoplastic progression in CeCa and its correlation with HPV infection. Materials and Methods: Expression of HOXB2 and HOXB13 proteins was assessed in tissue microarrays from normal cervical epithelium, cervical intraepithelial neoplasias grade 1-3, and CeCa. HPV was detected by PCR and sequencing. Expression of HOX-positive cells was determined in each diagnostic group. Results: Percentage of HOXB2- and HOXB13-positive cells gradually increased from means of 10.9% and 16.7%, respectively, in samples from healthy women, to 75.2% and 88.6% in those from CeCa patients. Frequency of HPV infection also increased from 13% in healthy tissue samples to 92.3% in CeCa. Both HOXB2 and HOXB13 proteins were preferentially expressed in HPV+ samples. Conclusions: The present study represents the first report on the expression of both HOXB2 and HOXB13 proteins through cervix tumorigenesis, providing evidence that increased expression of such proteins is a common event during progression to CeCa. more...

This paper presents alternatives for meeting the deficit in sugared substrates in a territory with several sugar mills and ethanol distilleries so they can reach their current production capacity. By using secondary currents and diluted juices from the sugar production process, wastage was first reduced to 26.92%. Then by optimizing the molasses linking and bagasse between sugar mills and ethanol distilleries, an important problem was resolved allowing production capacity to be met. This represented a 154.96% increase over what was initially planned. En el presente artículo se estudian diferentes alternativas para satisfacer el déficit de substratos azucarados, con el fin de lograr el uso planificado de la capacidad instalada de la producción de etanol en un área de varios ingenios y destilerías, primero minimizando el porcentaje de residuos en un 25,92%, a través del uso de corrientes secundarias y jugos diluidos, generados del proceso de producción de azúcar. La optimización del vínculo de mieles y del bagazo, entre los ingenios y las destilerías, permite resolver una importante incógnita que es el aprovechar la capacidad instalada durante todo el año, lo que significa incrementar el aprovechamiento hasta 154,96% de lo inicialmente planificado. more...

International audience; Broadcast is a fundamental operation in Mobile Ad-Hoc Networks (MANETs). A large variety of broadcast algorithms have been proposed. They differ in the way message forwarding between nodes is controlled, and in the level of information about the topology that this control requires. Deployment scenarios for MANETs vary widely, in particular in terms of nodes density and mobility. The choice of an algorithm depends on its expected coverage and energy cost, which are both impacted by the deployment context. In this work, we are interested in the comprehensive comparison of the costs and effectiveness of broadcast algorithms for MANETs depending on target environmental conditions. We describe the results of an experimental study of five algorithms, representative of the main design alternatives. Our study reveals that the best algorithm for a given situation, such as a high density and a stable network, is not necessarily the most appropriate for a different situation such as a sparse and mobile network. We identify the algorithms characteristics that are correlated with these differences and discuss the pros and cons of each design. more...

This chapter focuses on a deep description of the epidermal growth factor receptor (EGFR) expression in circulating tumor cells (CTCs) and its main role in cancer progression, genetic changes related to metastasis , and resistance to treatment. The aberrant behavior of cancer cells is caused by genetic mutations and altered patterns of gene expression. These changes can be responsible for an increase in cell motility but also an ability of CTCs to survival in different microenvironments, as well as developing therapy-resistant clones. Finally, CTCs can acquire the ability to invade distant organs, where metastatic foci can develop. more...

Cancer cells can divert metabolites into anabolic pathways to support their rapid proliferation and to accumulate the cellular building blocks required for tumour growth. However, the specific bioenergetic profile of invasive and metastatic cancer cells is unknown. Here we report that migratory/invasive cancer cells specifically favour mitochondrial respiration and increased ATP production. Invasive cancer cells use the transcription coactivator peroxisome proliferator-activated receptor gamma, coactivator 1 alpha (PPARGC1A, also known as PGC-1α) to enhance oxidative phosphorylation, mitochondrial biogenesis and the oxygen consumption rate. Clinical analysis of human invasive breast cancers revealed a strong correlation between PGC-1α expression in invasive cancer cells and the formation of distant metastases. Silencing of PGC-1α in cancer cells suspended their invasive potential and attenuated metastasis without affecting proliferation, primary tumour growth or the epithelial-to-mesenchymal program. Inherent genetics of cancer cells can determine the transcriptome framework associated with invasion and metastasis, and mitochondrial biogenesis and respiration induced by PGC-1α are also essential for functional motility of cancer cells and metastasis. more...

The human hearing system captures acoustic waves in air that are transmitted to the cochlea where are converted in nerve signal. Meanwhile, at the cochlea, some sensory cell are active provoking sound transmission in the reverse direction. These called otoacoustic emissions are measured in the ear canal as diagnostic method. Forward and reverse transmission mechanisms are complex being a matter of research. Its study presents great difficulty, either by experimental or numerical methods. A simplified experiment has been designed to evaluate both mechanisms. It consists of a system with the basic elements (air, tympanic membrane and ossicular chain).The present paper presents results corresponding to a previous numerical study. Methodology is described, it is based in previous work. Main results are shown in terms of modal analysis and sound pressure fields. Comparing with the behavior of a membrane , the presence of the umbo adds stiffness and mass to the system. Results prove that the effect of the mass is more significant, increasing the number of modes present in the range of frequency of interest. Comparing forward and reverse mechanisms, the main difference is on the side of the stimuli, similar to the opposite side. Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech more...

Fatigue crack closure has been studied by means of finite element method since long time ago. Most work has been performed considering bi-dimensional models. Lately, the use of threedimensional models has been extended. Nevertheless, the methodology employed has been taken from that developed for bi-dimensional cases. There are a great number of previous bi-dimensional studies which analyse different numerical parameters and optimise them. The current computational capabilities allow a comprehensive study of the influence of the different modelling parameters in a similar way to those studies carried out with bidimensional models, with the advantage, that the evolution along the thickness of the analysed parameters can be taken into consideration. In particular, one of the key issues is related to the plastic wake length which is developed during the previous loading cycles. This residual stresses have a great influence on the crack opening and closure values. As the numerical analysis are complex and computationally expensive, the length of the simulated wake is a critical parameter. In this work, a comprehensive study of the effect of the plastic wake in fatigue crack closure is made. On this purpose, a CT aluminium specimen has been modelled three-dimensionally and several calculations have been made in order to evaluate the influence of the simulated plastic wake length. The numerical analysis is made in terms of crack closure and opening values as in terms of the stress and strain fields near the crack front. Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. more...

In this paper, we studied four of the nine dimensions of organizational climate defined under the model proposed by Litwin and Stringer. These are structure, rewards, relationships and identity. We specifically examine the area of production of forest common land in El Brillante, Durango, Mexico in 2012. We surveyed 70 workers in the production area. The measuring instrument assessed four dimensions on the Likert scale. The Cronbach Alpha coefficient was determined with a 0.935 reliability. Dimensions were identified according to the staff evaluation of the organization. The results lead us to conclude that in the structure dimension, the staff agrees with the organizational common land structure. As for the reward dimension, it was identified that the common land has contributed positively in their motivation and provides the necessary training for the development of their work. For the relationship dimension it was observed that they are in harmony and have clear, precise and fluid communication. In the identity dimension, the staff feels as an important part that contributes to the achievement of common land goals and they enjoy working within it. more...

Distributed applications are evolving at a frantic pace, critically relying on integrating altogether a plethora of composable value-added services to offer a host of new functionalities. In previous work, we have introduced a language-based approach to raise the level of abstraction required to express an orchestration of services. Our prototype implementation has proved to be efficient when running on a single machine. In this paper, we report our experience in turning this prototype implementation into a commercial product, supporting horizontal scaling across a cluster of nodes.We perform a series of experiments to show that our approach overcomes API rate limit rules of third-party services and scales the number of executed composite services linearly with the number of nodes of the cluster. We show that our approach outperforms traditional off-the-shelf tools and techniques, such as the ones provided by Docker Swarm. more...

This paper presents a numerical study of the influence of the load level and the crack front curvature on the plastic zone in the area close to the crack front. The aim of the work is to determine the influence of these parameters on fatigue crack closure. For this, a CT aluminum specimen has been modelled tri-dimensionally and several finite elements calculations have been made considering a large combination of the variables under consideration. more...

Many mechanical components are subjected to multiaxial fatigue. These conditions are typically coming from external loads, the geometry of the component and/or residual stresses. However the majority of experimental data available in the literature are focused on the simpler uni-axial fatigue problem. The present work describes a series of experimental tests conducted to characterise in a comprehensive way the multiaxial behaviour of a ST52-3N structural steel. First, the monotonic properties of the steel were obtained experimentally. Then cyclic properties were also measured both in the longitudinal and torsional axes. Finally another series of tests were carried out to study the multiaxial response of the material. Both in-phase (proportional) and out-of-phase (non proportional) loadings were employed, thus providing a complete database for improving current models which describe the multiaxial behaviour of materials. more...

r Fatigue crack closure is strongly influenced by the plastic wake developed because of the action of precedent cycles. It is related to the load sequence and is an additional difficulty for its determination. Finite-element method has been an alternative for the study of crack closure, commonly in constant-amplitude loading. However, such analyses are complex and computationally expensive, the length of the wake simulated being a critical parameter. In this paper, a comprehensive study of the effect of the plastic wake in fatigue crack closure is made. It is structured in two parts: one regarding the correct numerical modelling process and the other focussed on the influence of the wake under moderate variable-amplitude loading. After a brief description of the numerical methodology, results for different wake lengths are reported. The plastic wake is modelled with a new approach in which the final crack tip is fixed. Information regarding potential error is provided. Second, the load sequence effect is discussed. Crack closure is obtained for several load ratios, with wakes developed with different stress ratios. This permits the analysis of the influence of the load sequence over the crack-driving force compared with constant-amplitude loading. more...