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Remote maintenance support with the aid of cyber-physical systems and cloud technology
Get PDFThis article discusses how a business model based on traditional maintenance can evolve to generate servitization strategies, with the help of remote maintenance support. The application of cyber-physical systems and cloud technologies play a key role for such maintenance purposes. In fact, the utilization of large quantities of data collected on machines and their processing by means of advanced techniques such as machine learning enable novel techniques for condition-based maintenance. New sensor solutions that could be used in maintenance and interaction with cyber-physical systems are also presented. Here, data models are an important part of these techniques because of the huge amounts of data that are produced and should be processed. These data models have been used in a real case, supported by the Machinery Information Management Open System Alliance Open System Architecture for Condition-Based Maintenance standard architecture, for streamlining the modeling of collected data. In this context, an industrial use case is described, to enlighten the application of the presented concepts in a working pilot. Finally, current and future directions for application of cyber-physical systems and cloud technologies to maintenance are discussed
Connotative meaning of travel modes and activity-travel behavior
Get PDFThis paper aims to present results of a study regarding how the meaning of travel modes influences on the performance of activities and trips.
Connotative meaning of travel modes was measured using semantic differential scales, which collect the suggestive significance of the terms used to name current travel modes. More than 400 people provided that information together with values and other types of attitudes, characteristics of their usual companions, socio-demographics, and 2-days activity-travel diary that includes a weekend day and a weekday.
Descriptive analysis, which include frequency distributions, Factor Analysis, and correlations, have been developed to find potential relations among the studied variables.
Maintenance activities are the most frequent, followed by discretionary activities. Only 10% of the total activities are mandatory. Approximately one third of trips are carried out by private vehicle. Motorized travel modes are characterized as noisy and powerful, in particular cars, while walking and cycling are simple and quiet
Impedance-Based Stability Evaluation of Virtual Synchronous Machine Implementations in Converter Controllers
Get PDFThis paper presents a stability evaluation of two Virtual Synchronous Machine (VSM) implementations in the control of Voltage Source Converters (VSCs): a current-controlled (CCVSM) and a voltage-controlled (VCVSM) version of the VSM. The performances of the two control implementations are analyzed under power reference and grid frequency variations and the evaluation of their stability properties is carried out by adopting the impedance-based stability analysis. The results of the dq impedance analysis of the two VSMs implementations reveal a clear differentiation between the CCVSM and the VCVSM, particularly in the very low frequency range, even if a close similarity is observed in the time domain responses. The dq impedances of both implementations show an RL behaviour in the medium frequency range, but when inspecting the stability margin on the Nyquist plot, the VCVSM appears to have a lower stability margin than the CCVSM from the intersection with the unit circle
Reconciling the Places Where We Live with the Spaces We Inhabit: Construction of a Communicative Space for Basque Based on a Local Media Network
Get PDFThe aim of this research is to give a detailed description of local media working in Basque language, hence, providing a backdrop for other minority language local media. Our approach is to offer data based on a questionnaire distributed among 65 local media with a response rate of 84%, ten in-depth interviews and a focus group. The data revealed a total publication of 200.000 copies with potential for a 70 page newspaper, 400.000 readers, almost 300 employees and more than 1.000 collaborating individuals. However, in spite of seeking to collaborate within a common framework, diversity and economic insecurity limit the potential of these local media groups to do so.The aim of this research is to give a detailed description of local media working in Basque language, hence, providing a backdrop for other minority language local media. Our approach is to offer data based on a questionnaire distributed among 65 local media with a response rate of 84%, ten in-depth interviews and a focus group. The data revealed a total publication of 200.000 copies with potential for a 70 page newspaper, 400.000 readers, almost 300 employees and more than 1.000 collaborating individuals. However, in spite of seeking to collaborate within a common framework, diversity and economic insecurity limit the potential of these local media groups to do so
El aprendizaje basado en retos de la formación profesional del País Vasco
Get PDFTras una breve contextualización del País Vasco, se describe en este artículo el modelo formativo ETHAZI (Ciclos de Alto Rendimiento en euskera/vasco) que está siendo desarrollado desde Tknika – Centro para la Investigación y la Innovación de la Formación Profesional – para dar respuesta a las nuevas demandas que se presentan en el ámbito laboral a partir de la globalización y el incremento exponencial de la tecnología
Experiencia Cooperativa de Mondragón: la educación cooperativa como un proceso de transformación social
Get PDFEste artículo pretende mostrar una propuesta de educación cooperativa potenciadora de la articulación
entre prácticas productivas y prácticas educativas, o sea, entre reflexión y acción, como factor potenciador
del proceso de enseñanza-aprendizaje para el desarrollo individual y social. La propuesta parte de una
investigación cualitativa – estudio de caso y observación participante – del Modelo de Educación Cooperativa del
movimiento cooperativo de Mondragon. La interpretación de los datos se ha llevado a cabo siguiendo la metodología
del Discurso del Sujeto Colectivo (DSC) con ayuda del software QualiQuantiSoft®. En esta propuesta se
vislumbra la educación cooperativa como factor de expresión y realización de los principios de la solidaridad y
transformación social para avanzar en los procesos de desarrollo territorial sostenible.The cooperativism is considered one of the main instruments of promotion of economic and
social development that creates and distributes wealth and promotes social capital in the
communities. The cooperative education in the development of competences attends to the
proposals of territorial development materialized in programs and projects that begin to have
meaning at the moment of its implementation. Even though the Mondragon Cooperative Experience
arouses interest after six decades, this paper does not aim to analyze its history, achievements,
contradictions, and challenges already analyzed and debated by literature. The objective is to
analyze the proposals in the field of cooperative education as an enhancing factor in the articulation
between productive and educational practices, it means, between reflection and action as a factor
that intensifies the teaching-learning process for individual and social development. The proposal is
based on a qualitative research, case study, and participant observation of the Cooperative
Education Model of Mondragon, from an exploratory-descriptive-evaluative view that was carried out
during a sandwich doctorate internship, in the years 2014-2015, resulting from the collaboration
between two graduate programs of Brazilian universities - PUCPR and FURB - and the Institute of
Cooperative Studies (Lanki) of Mondragón Unibertsitatea. To analyze the data was used the
methodology of the Collective Subject Discourse (CSD) and the QualiQuantiSoft® software. The
results show the cooperativism course of the Lanki: (1) Education processes are (re) construction
and strengthening of the cooperative identity in three parts: rational-intellectual, emotional-affective
and action. Lanki understands education as an integral and continuous process that encompasses
the development of all dimensions of the person through interaction with their social environment.
Understands education as a systematic and planned action that affects not only knowledge but also
attitudes and abilities through the experience of learning in a specific context. (2) Ecological
sustainability is a concern in this model but its reflection in practice is still far to become reality.
Responsible consumption based on ecological, ethical, and social criteria, is at the level of reflection
and not of action. The initiatives in this sense are still timid and incipient. The CSDs shows
difficulties with the transmission of knowledge and competence within the cooperatives as well as to
the application of the apprenticeship. The competencies for the implementation of learning are,
therefore, more limited. The main points based on the qualitative reading of the evaluations obtained
in the course are highlighted. The participants showed a high degree of interest. It is emphasized
overall, that the topics studied are of vital importance for the development of the cooperative. There
is a need to invigorate shared decision spaces to create a sense of belonging. Many of the participants acknowledge this feeling as such a certain “discovery”. It is emphasized that these
issues have not been properly worked on in the cooperatives and it is necessary to dedicate time to
them. The dialogue generated among the participants and the methodology used is particularly
valued. The cooperative course classes require more time. There is a clear demand to discuss
cooperativism dynamics from the social bases of the cooperatives. The cooperative education
should form, first of all, cooperative men and women and then form cooperatives leaderships. In this
analysis, it is concluded that the pedagogy of social practice of cooperative education, despite
having an interdisciplinary approach, has difficulties to advance from reflection to action, and from
discourse to practice. The development model in which the Mondragon cooperatives are immersed
is a factor that hinders progress towards the sustainability of the development model by focusing on
the environmental-ecological axis. One of the main challenges of the educational model analyzed is
promoting the abilities and competencies of individuals for resilience in the face of social and
ecological crisis. The paradigm of sustainable territorial development presupposes a set of
sustainability synthesized in the trinomial of economic efficiency, environmental and social
effectiveness. Despite the efforts to revitalize the socio-cooperative project, it cannot be ignored that
a socioeconomic model based on the paradigm of unlimited growth. It means, it cannot achieve a
sustainable territorial development without changes in the forms of production and consumption
without strengthening the socio-environmental effectiveness. The cooperative education model
requires a greater strengthening of praxis (articulation between theory and practice). It is necessary
in order to implement the pedagogy of social practice with inter and transdisciplinary vision, which
makes clear the interrelation of economic and biosphere processes. Environmental and social
sustainability will be the agenda of this century. Therefore, the cooperative education shall include
the environmental issues, so that produces transformations in modes of production, consumption,
and of life itself to create an awareness of the limits of economic rationality. Then, the ideal of human
self-realization and social emancipation inevitably arises from the integration of the socio-ecological
dimension. It can be said that cooperative education for the integral development of the person is a
broad concept that encompasses from technical, to social and ethical education. Education is a
central issue to the integral development and self-realization, promoting the autonomy, freedom, and
responsibility, which represent an enormous potential for transforming and emancipating people. On
the other hand, it contributes to the strengthening of anti-hegemonic values such as solidarity,
cooperation, and autonomy, promoting critical awareness, which is the basis of the processes with
an enormous transforming and emancipating potential. Arizmendiarrieta said that consciences had
to be transformed in structures. It means social emancipation that is conducted through cooperative
education as a critical pedagogy or for social transformation. It is concluded that new spaces are
needed for cooperative reflection where cooperative education should be a tool that encourages
space for debate, based on dialogical and participative dynamics to share and build cooperative
meaning. Cooperative education is an interesting tool to promote the debate and the collective
construction of proposals. The practice accumulated in recent years shows the lack of space to
recreate the cooperative identity. An important part of the cooperative is that the members should be
involved in the educational processes to assure the cooperative values. In this sense, cooperativism is characterized as a more humanized model of the economy, as the term social economy suggests.
Cooperative education, in turn, allows spaces for debate to work identity and cooperative practice,
develop feelings of belonging and affinity to the cooperative model. The cooperativism has the
greatest challenge of incorporating intergenerational rights, not only socioeconomic but also
environmental, with a more robust and resilient socio-business project in the face of climate change
Fe nanoparticles produced by electric explosion of wire for new generation of magneto-rheological fluids
Get PDFIron magnetic nanoparticles were produced by the technique of the electric explosion of a wire (EEW). The major crystalline phase (95 ± 1%) was α-Fe with lattice parameter a = 0.2863(3) nm. The size of the coherent diffraction domains of this phase was 77 ± 3 nm. The EEW MNPs presented a large saturation magnetization value, reaching about 87% of the saturation magnetization of the bulk iron. EEW NMPs demonstrated an improved magnetic performance when used in magnetorheological (MR) fluids with respect to the commercial carbonyl iron particles (CIPs) micron-sized particles studied for comparison. The MR fluids composed with the EEW nanoparticles showed larger yield stress values than those with CIP micron-sized particles, so proving that the EEW MNPs have a high potential for MR fluids applications
Dynamic DNS Request Monitoring of Android Applications via networking
Get PDFSmart devices are very popular and are becoming ubiquitous in the modern society, with Android OS as the most widespread operating system on current smartphones/tablets. However, malicious applications is one of the major concerns and fast growing security menaces facing the use of Internet in the Android platform, today. So, we need techniques and methods to address the massive malware attacks. One of the most relevant techniques to disclose sensitive behavior of Android applications during their runtime execution is Dynamic Analysis. Here we proposed a malware detection tool, termed as Network Sentinel, that it can be used for Dynamic DNS request Monitoring of Apps via networking. The main motivation for this work, it is extensively abuse of the DNS by malevolent communities in order to provide Internet connection within malicious networks and botnets. Finally, the experimental results obtained are promising by allowing us to capture the DNS queries requested by the smartphones to remote servers from the collected network traces at very low battery usage
A methodology for model-based verification of safety contracts and performance requirements
No full textThe verification of safety requirements becomes crucial in critical systems where human lives depend on their correct functioning. Formal methods have often been advocated as necessary to ensure the reliability of software systems, albeit with a considerable effort. In any case, such an effort is cost-effective when verifying safety-critical systems. Often, safety requirements are expressed using safety contracts, in terms of assumptions and guarantees.
To facilitate the adoption of formal methods in the safety-critical software industry, we propose a methodology based on well-known modelling languages such as the unified modelling language and object constraint language. The unified modelling language is used to model the software system while object constraint language is used to express the system safety contracts within the unified modelling language. In the proposed methodology a unified modelling language model enriched with object constraint language constraints is transformed to a Petri net model that enables us to formally verify such safety contracts. The methodology is evaluated on an industrial case study. The proposed approach allows an early safety verification to be performed, which increases the confidence of software engineers while designing the system
Thermodiffusion in Ternary Mixtures of Water/Ethanol/Triethylene Glycol: First Report on the DCMIX3-Experiments Performed on the International Space Station
Get PDFWe report on thermodiffusion experiments conducted on the International Space Station ISS during fall 2016. These experiments are part of the DCMIX (Diffusion and thermodiffusion Coefficients Measurements in ternary Mixtures) project, which aims at establishing a reliable data base of non-isothermal transport coefficients for selected ternary liquid mixtures. The third campaign, DCMIX3, focuses on aqueous systems with water/ethanol/triethylene glycol as an example, where sign changes of the Soret coefficient have already been reported for certain binary subsystems. Investigations have been carried out with the SODI (Selectable Optical Diagnostics Instrument) instrument, a Mach-Zehnder interferometer set up inside the Microgravity Science Glovebox in the Destiny Module of the ISS. Concentration changes within the liquids have been monitored in response to an external temperature gradient using phase-stepping interferometry. The complete data set has been made available in spring 2017. Due to additionally available measurement time, it was possible to collect a complete data set at 30∘C and an almost complete data set at 25∘C, which significantly exceeds the originally envisaged measurements at a single temperature only. All samples could be measured successfully. The SODI instrument and the DCMIX experiments have proven reliable and robust, allowing to extract meaningful data even in case of unforeseen laser instabilities. First assessments of the data quality have revealed six out of 31 runs with some problems in image contrast and/or phase step stability that will require more sophisticated algorithms. This publication documents all relevant parameters of the conducted experiments and also events that might have an influence on the final results. The compiled information is intended to serve as a starting point for all following data evaluations