Quantitative and ecological study of some grasshoppers population (Orth.: Acridoidea) in Sierra Espuña (Murcia, SE. España)

Utilizando diferentes técnicas estadísticas de análisis multivariante, entre ellas y de manera destacada el análisis binario discriminante («BDA», Binary Discriminat Analysis), se definen grupos ecológicos de poblaciones de saltamontes en relación con los tipos fisionómicos de vegetación de mayor relevancia en Sierra Espuña. Se estudian relaciones entre especies, y se confirma como fundamental el tipo de vegetación como factor ambiental determinante de la distribución de las poblaciones y comunidades de acrídidos. Se esquematizan los resultados de un cuadro-resumen de preferencias: poblaciones de saltamontes- vegetación.Using some different statistical techniques of multivariate analysis, mainly Binary Discriminant Analysis (BDA), ecological groups of grasshoppers populations have been defined and related to the main physiognomic vegetation types of Sierra Espuña. The relationships between species have also been studied and it has been confirmed that the type of vegetation is a fundamental factor in determining the distribution of populations and communities of Acridoidea. Results are summarized in a comprehensive table that shows the preferences of grasshoppers populations and vegetation

Online machine learning algorithms to predict link quality in community wireless mesh networks

Producción CientíficaAccurate link quality predictions are key in community wireless mesh networks (CWMNs) to improve the performance of routing protocols. Unlike other techniques, online machine learning algorithms can be used to build link quality predictors that are adaptive without requiring a predeployment effort. However, the use of these algorithms to make link quality predictions in a CWMN has not been previously explored. This paper analyses the performance of 4 well-known online machine learning algorithms for link quality prediction in a CWMN in terms of accuracy and computational load. Based on this study, a new hybrid online algorithm for link quality prediction is proposed. The evaluation of the proposed algorithm using data from a real large scale CWMN shows that it can achieve a high accuracy while generating a low computational load.Ministerio de Economía, Industria y Competitividad (Project TIN2014-53199-C3-2-R)Junta de Castilla y León (programa de apoyo a proyectos de investigación - Ref. VA082U16

A self-scalable distributed network simulation environment based on cloud computing

Producción CientíficaWhile parameter sweep simulations can help undergraduate students and researchers to understand computer networks, their usage in the academia is hindered by the significant computational load they convey. This paper proposes DNSE3, a service oriented computer network simulator that, deployed in a cloud computing infrastructure, leverages its elasticity and pay-per-use features to compute parameter sweeps. The performance and cost of using this application is evaluated in several experiments applying different scalability policies, with results that meet the demands of users in educational institutions. Additionally, the usability of the application has been measured following industry standards with real students, yielding a very satisfactory user experience.Ministerio de Economía, Industria y Competitividad (Projects TIN2014-53199-C3-2-R and TIN2017-85179-C3-2-R)Junta de Castilla y León (programa de apoyo a proyectos de investigación - Ref. VA082U16

A Game-Theory method to design job rotation schedules to prevent musculoskeletal disorders Based on workers preferences and competencies

[EN] Job rotation is an organizational strategy based on the systematic exchange of workers between jobs in a planned manner according to specific criteria. This study presents the GS-Rot method, a method based on Game Theory, in order to design job rotation schedules by considering not only workers' job preferences, but also the competencies required for different jobs. With this approach, we promote workers' active participation in the design of the rotation plan. It also let us deal with restrictions in assigning workers to job positions according to their disabilities (temporal or permanent). The GS-Rot method has been implemented online and applied to a case in a work environment characterized by the presence of a high repetition of movements, which is a significant risk factor associated with work-related musculoskeletal disorders (WMSDs). A total of 17 workstations and 17 workers were involved in the rotation, four of them with physical/psychological limitations. Feasible job rotation schedules were obtained in a short time (average time 27.4 milliseconds). The results indicate that in the rotations driven by preference priorities, almost all the workers (94.11%) were assigned to one of their top five preferences. Likewise, 48.52% of job positions were assigned to workers in their top five of their competence lists. When jobs were assigned according to competence, 58.82% of workers got an assignment among their top five competence lists. Furthermore, 55.87% of the workers achieved jobs in their top five preferences. In both rotation scenarios, the workers varied performed jobs, and fatigue accumulation was balanced among them. The GS-Rot method achieved feasible and uniform solutions regarding the workers' exposure to job repetitiveness.This research was funded by the Erasmus+ program of the European Commission under Grant 2017-1-ES01-KA203-038589 in the frame of the project CoSki21-Core Skills for 21th-century professionals.Asensio-Cuesta, S.; Garcia-Gomez, JM.; Poza-Lujan, J.; Conejero, JA. (2019). A Game-Theory method to design job rotation schedules to prevent musculoskeletal disorders Based on workers preferences and competencies. International Journal of Environmental research and Public Health. 16(23):1-16. https://doi.org/10.3390/ijerph16234666S1161623Aptel, M., Cail, F., Gerling, A., & Louis, O. (2008). Proposal of parameters to implement a workstation rotation system to protect against MSDs. International Journal of Industrial Ergonomics, 38(11-12), 900-909. doi:10.1016/j.ergon.2008.02.006Jeon, I. S., Jeong, B. Y., & Jeong, J. H. (2016). Preferred 11 different job rotation types in automotive company and their effects on productivity, quality and musculoskeletal disorders: comparison between subjective and actual scores by workers’ age. Ergonomics, 59(10), 1318-1326. doi:10.1080/00140139.2016.1140816Botti, L., Mora, C., & Calzavara, M. (2017). Design of job rotation schedules managing the exposure to age-related risk factors. IFAC-PapersOnLine, 50(1), 13993-13997. doi:10.1016/j.ifacol.2017.08.2420Sixth European Working Conditions Survey-6th EWCS-Spainhttps://www.eurofound.europa.eu/surveys/european-working-conditions-surveys/sixth-european-working-conditions-survey-2015/ewcs-2015-methodologyAsensio-Cuesta, S., Diego-Mas, J. A., Canós-Darós, L., & Andrés-Romano, C. (2011). A genetic algorithm for the design of job rotation schedules considering ergonomic and competence criteria. The International Journal of Advanced Manufacturing Technology, 60(9-12), 1161-1174. doi:10.1007/s00170-011-3672-0Yoon, S.-Y., Ko, J., & Jung, M.-C. (2016). A model for developing job rotation schedules that eliminate sequential high workloads and minimize between-worker variability in cumulative daily workloads: Application to automotive assembly lines. Applied Ergonomics, 55, 8-15. doi:10.1016/j.apergo.2016.01.011Otto, A., & Scholl, A. (2012). Reducing ergonomic risks by job rotation scheduling. OR Spectrum, 35(3), 711-733. doi:10.1007/s00291-012-0291-6Carnahan, B. J., Redfern, M. S., & Norman, B. (2000). Designing safe job rotation schedules using optimization and heuristic search. Ergonomics, 43(4), 543-560. doi:10.1080/001401300184404Song, J., Lee, C., Lee, W., Bahn, S., Jung, C., & Yun, M. H. (2016). Development of a job rotation scheduling algorithm for minimizing accumulated work load per body parts. Work, 53(3), 511-521. doi:10.3233/wor-152232Boenzi, F., Digiesi, S., Facchini, F., & Mummolo, G. (2016). Ergonomic improvement through job rotations in repetitive manual tasks in case of limited specialization and differentiated ergonomic requirements. IFAC-PapersOnLine, 49(12), 1667-1672. doi:10.1016/j.ifacol.2016.07.820Sana, S. S., Ospina-Mateus, H., Arrieta, F. G., & Chedid, J. A. (2018). Application of genetic algorithm to job scheduling under ergonomic constraints in manufacturing industry. Journal of Ambient Intelligence and Humanized Computing, 10(5), 2063-2090. doi:10.1007/s12652-018-0814-3Burgess-Limerick, R. (2018). Participatory ergonomics: Evidence and implementation lessons. Applied Ergonomics, 68, 289-293. doi:10.1016/j.apergo.2017.12.009Bhuiyan, B. A. (2018). An Overview of Game Theory and Some Applications. Philosophy and Progress, 111-128. doi:10.3329/pp.v59i1-2.36683Gale, D., & Shapley, L. S. (1962). College Admissions and the Stability of Marriage. The American Mathematical Monthly, 69(1), 9-15. doi:10.1080/00029890.1962.11989827Roth, A. E. (2008). What Have We Learned from Market Design? The Economic Journal, 118(527), 285-310. doi:10.1111/j.1468-0297.2007.02121.xRoth, A. E., & Sotomayor, M. (1992). Chapter 16 Two-sided matching. Handbook of Game Theory with Economic Applications, 485-541. doi:10.1016/s1574-0005(05)80019-0Renna, P. (2017). Decision-making method of reconfigurable manufacturing systems’ reconfiguration by a Gale-Shapley model. Journal of Manufacturing Systems, 45, 149-158. doi:10.1016/j.jmsy.2017.09.005Butkovič, P., & Lewis, S. (2007). On the job rotation problem. Discrete Optimization, 4(2), 163-174. doi:10.1016/j.disopt.2006.11.00

Understanding student behavior and perceptions toward earning badges in a gamified MOOC

Producción CientíficaDespite the advantages of MOOCs, such as the open and free access to education, these courses are criticized for students’ lack of motivation and their high dropout rates. Gamification is a technique used to increase student motivation and engagement in small-scale educational contexts. However, the effects of gamification on student engagement have been scarcely explored in MOOC environments, and the findings so far are inconsistent. To address this gap, this research work examines the students’ behavior toward earning badges and how it relates to their engagement in a gamified MOOC. According to the results, the behaviors toward badges of the active students were generally positive and significantly correlated with other variables measuring their engagement (e.g., pageviews, submitted tasks, forum posts), although this positive behavior seems to decrease throughout the course. Additionally, students that reported high motivation by badges at the end of the course showed a higher engagement level than those that were not appealed by badges.European Regional Development Fund, under project grants TIN2014-53199-C3-2-R and TIN2017-85179-C3-2-RJunta de Castilla y León (programa de apoyo a proyectos de investigación - Ref. Project VA082U16 and VA257P18)European Commission, under project grant 588438-EPP-1-2017-1-EL-EPPKA2-KA

Awareness: A parallel approach against noise

Unlike other pollutants, many of the noise effects on people have a clear subjective component that go beyond the objective physiological effects that the physical phenomenon causes. Among them, annoyance is the most documented subjective response to noise, it being defined as a feeling of discomfort or displeasure that occurs when noise intrudes our everyday activities. For decades it has been one of the hot topics of environmental acoustics. But, while many studies have focused on the possible correlation between sound metrics and the adverse reaction of the population, the effect of non-acoustic factors on the annoyance response has recently emerged as a hot topic in international transport research groups. The aim of this paper is to present a novel approach to the assessment of noise impacts that could be of value to railway operations, complementing traditional approaches based on the reduction of exposure. Awareness comprises several non-acoustical factors pointed out in the past as affecting annoyance: information (accessibility, transparency and understanding), trust, influence/voice, attitude towards the source, predictability of the noise situation, awareness of negative effects... The project aims to obtain knowledge of this factor, analyse its influence, and take advantage of it to mitigate annoyance. This is an approach that has not been exploited in depth in the past, and does not imply the reduction of noise emissions at all, so that it can be managed together with other noise control measures. It is based on the hypothesis that "bringing information closer to residents will reduce noise annoyance", and tries to answer the following question: How does Awareness Influence Noise Annoyance? To what extent can Communication or other Non-Acoustical measures modify Awareness in order to help residents to cope with Noise

Glycosyl Oxocarbenium Ions: Structure, Conformation, Reactivity, and Interactions

Conspectus We also highlight that, from a chemical perspective, the glycosylation reaction can be described as a continuum, from unimolecular SN1 with naked oxocarbenium cations as intermediates to bimolecular SN2-type mechanisms, which involve the key role of counterions and donors. All these factors should be considered and are discussed herein. The importance of dissociative mechanisms (involving contact ion pairs, solvent-separated ion pairs, solvent-equilibrated ion pairs) with bimolecular features in most reactions is also highlighted. The role of theoretical calculations to predict the conformation, dynamics, and reactivity of the oxocarbenium ion is also discussed, highlighting the advances in this field that now allow access to the conformational preferences of a variety of oxocarbenium ions and their reactivities under SN1-like conditions. Specifically, the ground-breaking use of superacids to generate these cations is emphasized, since it has permitted characterization of the structure and conformation of a variety of glycosyl oxocarbenium ions in superacid solution by NMR spectroscopy. We also pay special attention to the reactivity of these glycosyl ions, which depends on the conditions, including the counterions, the possible intra- or intermolecular participation of functional groups that may stabilize the cation and the chemical nature of the acceptor, either weak or strong nucleophile. We discuss recent investigations from different experimental perspectives, which identified the involved ionic intermediates, estimating their lifetimes and reactivities and studying their interactions with other molecules. In this context, we also emphasize the relationship between the chemical methods that can be employed to modulate the sensitivity of glycosyl cations and the way in which glycosyl modifying enzymes (glycosyl hydrolases and transferases) build and cleave glycosidic linkages in nature. This comparison provides inspiration on the use of molecules that regulate the stability and reactivity of glycosyl cations

Generating actionable predictions regarding MOOC learners’ engagement in peer reviews

Producción CientíficaPeer review is one approach to facilitate formative feedback exchange in MOOCs; however, it is often undermined by low participation. To support effective implementation of peer reviews in MOOCs, this research work proposes several predictive models to accurately classify learners according to their expected engagement levels in an upcoming peer-review activity, which offers various pedagogical utilities (e.g. improving peer reviews and collaborative learning activities). Two approaches were used for training the models: in situ learning (in which an engagement indicator available at the time of the predictions is used as a proxy label to train a model within the same course) and transfer across courses (in which a model is trained using labels obtained from past course data). These techniques allowed producing predictions that are actionable by the instructor while the course still continues, which is not possible with post-hoc approaches requiring the use of true labels. According to the results, both transfer across courses and in situ learning approaches have produced predictions that were actionable yet as accurate as those obtained with cross validation, suggesting that they deserve further attention to create impact in MOOCs with real-world interventions. Potential pedagogical uses of the predictions were illustrated with several examples.European Union’s Horizon 2020 research and innovation programme (Marie Sklodowska-Curie grant 793317)Ministerio de Ciencia, Innovación y Universidades (projects TIN2017-85179-C3-2-R / TIN2014-53199-C3-2-R)Junta de Castilla y León (grant VA257P18)Comisión Europea (grant 588438-EPP-1-2017-1-EL-EPPKA2-KA

Towards the Enactment of Learning Situations Connecting Formal and Non-Formal Learning in SLEs

Producción CientíficaSmart Learning Environments hold promise of adapting learning processes to the individual context of students and connecting formal with non-formal learning. To do so, SLEs need to know the current context of the students, regardless of the physical or virtual space where learning takes place. This paper presents an architecture that assists in the deployment and enactment of learning situations across-spaces, able to sense and react to changes in the students’ context in order to adapt the learning process.ICSLE 2019: International Conference on Smart Learning EnvironmentsAgencia Estatal de Investigación - Fondo Europeo de Desarrollo Regional (projects TIN2014-53199-C3-2-R / TIN2017-85179-C3-2-R)Comisión Europea (project 588438-EPP-1-2017-1-EL-EPPKA2-KA