Designing Cyclic Job Rotations to Reduce the Exposure to Ergonomics Risk Factors

[EN] Job rotation is an administrative solution to prevent work-related musculoskeletal disorders that has become widespread. However, job rotation schedules development is a complex problem. This is due to the multi-factorial character of the disorders and to the productive and organizational constraints of the real working environments. To avoid these problems, this work presents an evolutionary algorithm to generate rotation schedules in which a set of workers rotate cyclically over a small number of jobs while reducing the potential for injury. The algorithm is able to generate rotation schedules that optimize multiple ergonomics criteria by clustering the tasks into rotation groups, selecting the workers for each group, and determining the sequence of rotation of the workers to minimize the effects of fatigue. The algorithm reduces prolonged exposure to risks related to musculoskeletal injuries and simplifies the assignment of workers to different tasks in each rotation. The presented procedure can be an effective tool for the design of job-rotation schedules that prevent work-related musculoskeletal disorders while simplifying scheduled changeovers at each rotation and facilitating job monitoring.Diego-Mas, JA. (2020). Designing Cyclic Job Rotations to Reduce the Exposure to Ergonomics Risk Factors. International Journal of Environmental research and Public Health. 17(3):1-17. https://doi.org/10.3390/ijerph17031073S117173Ouellet, S., & Vézina, N. (2003). L’implantation de la rotation de postes : un exemple de démarche préalable. Perspectives interdisciplinaires sur le travail et la santé, (5-2). doi:10.4000/pistes.3322Bhadury, J., & Radovilsky, Z. (2006). Job rotation using the multi-period assignment model. International Journal of Production Research, 44(20), 4431-4444. doi:10.1080/00207540500057621Jeon, 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:10.1080/00140139.2016.1140816Van Wyk, A. E., Swarts, I., & Mukonza, C. (2018). The Influence of the Implementation of Job Rotation on Employees’ Perceived Job Satisfaction. International Journal of Business and Management, 13(11), 89. doi:10.5539/ijbm.v13n11p89Rissén, D., Melin, B., Sandsjö, L., Dohns, I., & Lundberg, U. (2002). Psychophysiological stress reactions, trapezius muscle activity, and neck and shoulder pain among female cashiers before and after introduction of job rotation. Work & Stress, 16(2), 127-137. doi:10.1080/02678370210141530Allwood, J. M., & Lee, W. L. (2004). The impact of job rotation on problem solving skills. International Journal of Production Research, 42(5), 865-881. doi:10.1080/00207540310001631566McDonald, T., Ellis, K. P., Van Aken, E. M., & Patrick Koelling, C. (2009). Development and application of a worker assignment model to evaluate a lean manufacturing cell. International Journal of Production Research, 47(9), 2427-2447. doi:10.1080/00207540701570174Costa, A. M., & Miralles, C. (2009). Job rotation in assembly lines employing disabled workers. International Journal of Production Economics, 120(2), 625-632. doi:10.1016/j.ijpe.2009.04.013Schneider, S., Grant, K. A., Habes, D. J., & Bertsche, P. K. (1997). Ergonomics: Lifting Hazards at a Cabinet Manufacturing Company: Evaluation and Recommended Controls. Applied Occupational and Environmental Hygiene, 12(4), 253-258. doi:10.1080/1047322x.1997.10389500Comper, M. L. C., & Padula, R. S. (2014). The effectiveness of job rotation to prevent work-related musculoskeletal disorders: protocol of a cluster randomized clinical trial. BMC Musculoskeletal Disorders, 15(1). doi:10.1186/1471-2474-15-170KUIJER, P. P. F. M., VISSER, B., & KEMPER, H. C. G. (1999). Job rotation as a factor in reducing physical workload at a refuse collecting department. Ergonomics, 42(9), 1167-1178. doi:10.1080/001401399185054Hinnen, U., Laubli, T., Guggenbuhl, U., & Krueger, H. (1992). Design of check-out systems including laser scanners for sitting work posture. Scandinavian Journal of Work, Environment & Health, 18(3), 186-194. doi:10.5271/sjweh.1589Kuijer, P. P. F. M., van der Beek, A. J., van Dieën, J. H., Visser, B., & Frings-Dresen, M. H. W. (2005). Effect of job rotation on need for recovery, musculoskeletal complaints, and sick leave due to musculoskeletal complaints: A prospective study among refuse collectors. American Journal of Industrial Medicine, 47(5), 394-402. doi:10.1002/ajim.20159Frazer, M., Norman, R., Wells, R., & Neumann, P. (2003). The effects of job rotation on the risk of reporting low back pain. Ergonomics, 46(9), 904-919. doi:10.1080/001401303000090161Asensio-Cuesta, S., Diego-Mas, J. A., Cremades-Oliver, L. V., & González-Cruz, M. C. (2012). A method to design job rotation schedules to prevent work-related musculoskeletal disorders in repetitive work. International Journal of Production Research, 50(24), 7467-7478. doi:10.1080/00207543.2011.653452Vinel, A., Mehdizadeh, A., Schall, M. C., Gallagher, S., & Sesek, R. F. (2018). An Optimization Framework for Job Rotation to Better Assess the Impact on Overall Risk. Proceedings of the Human Factors and Ergonomics Society Annual Meeting, 62(1), 843-847. doi:10.1177/1541931218621192Kher, H. V., Malhotra, M. K., Philipoom, P. R., & Fry, T. D. (1999). Modeling simultaneous worker learning and forgetting in dual resource constrained systems. European Journal of Operational Research, 115(1), 158-172. doi:10.1016/s0377-2217(98)00190-8Eriksson, T., & Ortega, J. (2006). The Adoption of Job Rotation: Testing the Theories. ILR Review, 59(4), 653-666. doi:10.1177/001979390605900407Jeon, I. S., & Jeong, B. Y. (2016). Effect of Job Rotation Types on Productivity, Accident Rate, and Satisfaction in the Automotive Assembly Line Workers. Human Factors and Ergonomics in Manufacturing & Service Industries, 26(4), 455-462. doi:10.1002/hfm.20667Song, 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-152232Yoon, 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.2016.01.011Padula, R. S., Comper, M. L. C., Sparer, E. H., & Dennerlein, J. T. (2017). Job rotation designed to prevent musculoskeletal disorders and control risk in manufacturing industries: A systematic review. Applied Ergonomics, 58, 386-397. doi:10.1016/j.apergo.2016.07.018Azizi, N., Zolfaghari, S., & Liang, M. (2010). Modeling job rotation in manufacturing systems: The study of employee’s boredom and skill variations. International Journal of Production Economics, 123(1), 69-85. doi:10.1016/j.ijpe.2009.07.010Carnahan, B. J., Redfern, M. S., & Norman, B. (2000). Designing safe job rotation schedules using optimization and heuristic search. Ergonomics, 43(4), 543-560. doi:10.1080/001401300184404Tharmmaphornphilas, W., & Norman, B. A. (2007). A methodology to create robust job rotation schedules. Annals of Operations Research, 155(1), 339-360. doi:10.1007/s10479-007-0219-8Seçkiner, S. U., & Kurt, M. (2007). A simulated annealing approach to the solution of job rotation scheduling problems. Applied Mathematics and Computation, 188(1), 31-45. doi:10.1016/j.amc.2006.09.082Seçkiner, S. U., & Kurt, M. (2008). Ant colony optimization for the job rotation scheduling problem. Applied Mathematics and Computation, 201(1-2), 149-160. doi:10.1016/j.amc.2007.12.006Yaoyuenyong, S., & Nanthavanij, S. (2006). Hybrid procedure to determine optimal workforce without noise hazard exposure. Computers & Industrial Engineering, 51(4), 743-764. doi:10.1016/j.cie.2006.08.018Diego-Mas, J. A., Asensio-Cuesta, S., Sanchez-Romero, M. A., & Artacho-Ramirez, M. A. (2009). A multi-criteria genetic algorithm for the generation of job rotation schedules. International Journal of Industrial Ergonomics, 39(1), 23-33. doi:10.1016/j.ergon.2008.07.009Asensio-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/s00170-011-3672-0Sana, 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/s12652-018-0814-3Digiesi, S. D., Facchini, F., Mossa, G., … Mummolo, G. (2018). Minimizing and Balancing Ergonomic Risk of Workers of an Assembly Line by Job Rotation: a MINLP Model. International Journal of Industrial Engineering and Management, 9(3), 129-138. doi:10.24867/ijiem-2018-3-129Crawford, J. O. (2007). The Nordic Musculoskeletal Questionnaire. Occupational Medicine, 57(4), 300-301. doi:10.1093/occmed/kqm03

Single users' affective responses models for product form design

This paper presents a neural network based approach to modeling consumers' affective responses for product form design. A theoretical framework for a single user's perception is developed. On the basis of this theoretical framework, a mathematical model which enables single users' responses to different products to be predicted was developed. The results obtained show that the mathematical models developed achieved highly accurate predictions. For the purpose of obtaining a global model various individual mathematical models were created, which were based on the opinions of users representing different groups of opinion. The results suggest that, under some conditions, the combined use of various models of individual users can perform as well as a single model generated on the basis of mean market responses.Diego-Mas, JA.; Alcaide Marzal, J. (2016). Single users' affective responses models for product form design. International Journal of Industrial Ergonomics. 53:102-114. doi:10.1016/j.ergon.2015.11.005S1021145

Measuring the Project Management Complexity: The Case of Information Technology Projects

[EN] Complex projects require specific project management (PM) competences development. However, while no complex projects have standards that are recognized to guide their management, complex projects do not have guides to deal with their complexity. To lead complex projects to success, this complexity must be measured quantitatively and, in our opinion, project management complexity assessment should be based on existing PM standards. In this work, the main project complexity assessment approaches based on PM standards are analyzed, observing that International Project Management Association (IPMA) approach is the closest to a tool that can be used as a complexity quantitative measurement system. On the other hand, several authors have shown that the inherent complexity of specific kind of projects must be measured in a particular way. The main objective of this research is to propose a project management complexity assessment tool for IT projects, providing a Complexity Index that measures the impact that complexity factors inherent to IT projects have under a specific complexity scenario. The tool combines the use of complexity factors defined by IPMA approach and the use of complexity factors found in the literature to manage inherent complexity of IT projects. All these factors were validated by expert survey and the tool was applied to a study case.Poveda Bautista, R.; Diego-Mas, JA.; Leon Medina, DA. (2018). Measuring the Project Management Complexity: The Case of Information Technology Projects. Complexity. 2018:1-19. https://doi.org/10.1155/2018/6058480S119201

Introducció a la mitologia grega per a alumnes de Primària

Treball Final de Grau en Mestre o Mestra d'Educació Primària. Codi: MP1040. Curs acadèmic: 2019/2020L’objectiu d’aquest treball és mostrar amb gran detall una proposta didàctica on els xiquets puguen gaudir a la vegada que adquireixen coneixements d’una de les civilitzacions més importants de la història, la Grega. Més concretament, a través de la seva mitologia i els deus més importants d’aquesta

Programa preventivo de habilidades sociales en la violencia escolar en estudiantes de primero de secundaria de una institución educativa

Este trabajo de investigación tiene como objetivo principal demostrar los efectos del programa preventivo de habilidades sociales en la violencia escolar en estudiantes de primero de secundaria de la institución educativa estatal del distrito de Trujillo, de edades entre 12 y 13 años. La muestra de estudio es de 40 estudiantes, de sexo masculino, distribuidos de manera equitativa en grupo experimental (n = 20) y en grupo control (n = 20). Los datos se recolectaron a través del cuestionario Auto-test Cisneros de acoso escolar. Los resultados evidencian que la ejecución del programa preventivo basado en habilidades sociales y ejecutadas sólo con el grupo experimental, realizó mejorías en el comportamiento de los estudiantes que ejercen la violencia escolar ya que su efecto fue de .40 según el efecto de Rosenthal, colocándolo en un nivel moderado. Además, también se obtuvieron mejoras a nivel de dimensión de la variable mencionada, obteniendo puntajes que van desde .35 a .40 categorizados como nivel moderado de acuerdo con el efecto de Rosenthal. Por ello, se afirma que este programa preventivo contribuye a la reducción de los comportamientos violentos en cualquiera de sus dimensiones

Errors Using Observational Methods for Ergonomics Assessment in Real Practice

[EN] Objective: The degree in which practitioners use the observational methods for musculoskeletal disorder risks assessment correctly was evaluated. Background: Ergonomics assessment is a key issue for the prevention and reduction of work-related musculoskeletal disorders in workplaces. Observational assessment methods appear to be better matched to the needs of practitioners than direct measurement methods, and for this reason, they are the most widely used techniques in real work situations. Despite the simplicity of observational methods, those responsible for assessing risks using these techniques should have some experience and know-how in order to be able to use them correctly. Method: We analyzed 442 risk assessments of actual jobs carried out by 290 professionals from 20 countries to determine their reliability. Results: The results show that approximately 30% of the assessments performed by practitioners had errors. In 13% of the assessments, the errors were severe and completely invalidated the results of the evaluation. Conclusion: Despite the simplicity of observational method, approximately 1 out of 3 assessments conducted by practitioners in actual work situations do not adequately evaluate the level of potential musculoskeletal disorder risks. Application: This study reveals a problem that suggests greater effort is needed to ensure that practitioners possess better knowledge of the techniques used to assess work-related musculoskeletal disorder risks and that laws and regulations should be stricter as regards qualifications and skills required by professionals.This work was supported by the Programa estatal de investigacion, desarrollo e innovacion orientada a los retos de la sociedad of the government of Spain under Grant DPI2016-79042-R.Diego-Mas, JA.; Alcaide Marzal, J.; Poveda Bautista, R. (2017). Errors Using Observational Methods for Ergonomics Assessment in Real Practice. Human Factors The Journal of the Human Factors and Ergonomics Society. 59(8):1173-1187. https://doi.org/10.1177/00187208177234961173118759

Propiedades psicométricas de la escala de detección de sexismo en adolescentes de secundaria del Distrito de Florencia de Mora

La presente investigación tuvo como finalidad determinar las propiedades psicométricas de la escala de detección de sexismo en adolescentes de secundaria del distrito de Florencia de Mora. La muestra se constituyó de 358 alumnos de ambos sexos del 3°, 4° y 5° año de secundaria, de edades entre 14 y 17 años. Se estableció evidencia de validez basada en la estructura interna con el método de análisis factorial confirmatorio comprobando que existe un ajuste satisfactorio en la estructura del instrumento estimado en comparación a la estructura establecida por los autores. Por otro lado, se obtuvo la confiabilidad a través de las cargas factorial omega, adquiriendo puntajes de .808 en la escala de Sexismo Benévolo y .876 en la escala de Sexismo Hostil

Effects of Using Immersive Media on the Effectiveness of Training to Prevent Ergonomics Risks

[EN] In this work, the effects of using immersive media such as virtual reality on the performance of training programs to avoid ergonomics risks are analyzed. The advance of technology has made it possible to use low-cost portable devices able to generate highly immersive experiences in training programs. The effects of using this kind of device in training programs have been studied in several fields such as industrial security, medicine and surgery, rehabilitation, or construction. However, there is very little research on the effects of using immersive media in training workers to avoid ergonomics risk factors. In this study, we compare the effects of using traditional and immersive media in a training program to avoid three common ergonomics risk factors in industrial environments. Our results showed that using immersive media increases the participant's engagement during the training. In the same way, the learning contents are perceived as more interesting and useful and are better remembered over time, leading to an increased perception of the ergonomics risks among workers. However, we found that little training was finally transferred to the workplace three months after the training session.This research was funded by Spanish Ministry of Economy, Industry and Competitiveness, grant number DPI2016-79042-R.Diego-Mas, JA.; Alcaide-Marzal, J.; Poveda Bautista, R. (2020). Effects of Using Immersive Media on the Effectiveness of Training to Prevent Ergonomics Risks. International Journal of Environmental research and Public Health (Online). 17(7):1-18. https://doi.org/10.3390/ijerph17072592S118177Perruccio, A. V., Yip, C., Badley, E. M., & Power, J. D. (2017). Musculoskeletal Disorders: A Neglected Group at Public Health and Epidemiology Meetings? American Journal of Public Health, 107(10), 1584-1585. doi:10.2105/ajph.2017.303990Merkesdal, S., Ruof, J., Huelsemann, J. L., Mittendorf, T., Handelmann, S., Mau, W., & Zeidler, H. (2005). Indirect cost assessment in patients with rheumatoid arthritis (RA): Comparison of data from the health economic patient questionnaire HEQ-RA and insurance claims data. Arthritis & Rheumatism, 53(2), 234-240. doi:10.1002/art.21080Gignac, M. A. M., Cao, X., Lacaille, D., Anis, A. H., & Badley, E. M. (2008). Arthritis-related work transitions: A prospective analysis of reported productivity losses, work changes, and leaving the labor force. Arthritis & Rheumatism, 59(12), 1805-1813. doi:10.1002/art.24085Daniels, K., Gedikli, C., Watson, D., Semkina, A., & Vaughn, O. (2017). Job design, employment practices and well-being: a systematic review of intervention studies. Ergonomics, 60(9), 1177-1196. doi:10.1080/00140139.2017.1303085Burgess-Limerick, R. (2018). Participatory ergonomics: Evidence and implementation lessons. Applied Ergonomics, 68, 289-293. doi:10.1016/j.apergo.2017.12.009King, P. M., Fisher, J. C., & Garg, A. (1997). Evaluation of the impact of employee ergonomics training in industry. Applied Ergonomics, 28(4), 249-256. doi:10.1016/s0003-6870(96)00067-1Burke, M. J., Sarpy, S. A., Smith-Crowe, K., Chan-Serafin, S., Salvador, R. O., & Islam, G. (2006). Relative Effectiveness of Worker Safety and Health Training Methods. American Journal of Public Health, 96(2), 315-324. doi:10.2105/ajph.2004.059840Ricci, F., Chiesi, A., Bisio, C., Panari, C., & Pelosi, A. (2016). Effectiveness of occupational health and safety training. Journal of Workplace Learning, 28(6), 355-377. doi:10.1108/jwl-11-2015-0087Brisson, C., Montreuil, S., & Punnett, L. (1999). Effects of an ergonomic training program on workers with video display units. Scandinavian Journal of Work, Environment & Health, 25(3), 255-263. doi:10.5271/sjweh.432Hogan, D. A. M., Greiner, B. A., & O’Sullivan, L. (2014). The effect of manual handling training on achieving training transfer, employee’s behaviour change and subsequent reduction of work-related musculoskeletal disorders: a systematic review. Ergonomics, 57(1), 93-107. doi:10.1080/00140139.2013.862307Yu, W., Yu, I. T. S., Wang, X., Li, Z., Wan, S., Qiu, H., … Sun, T. (2012). Effectiveness of participatory training for prevention of musculoskeletal disorders: a randomized controlled trial. International Archives of Occupational and Environmental Health, 86(4), 431-440. doi:10.1007/s00420-012-0775-3Hoe, V. C., Urquhart, D. M., Kelsall, H. L., Zamri, E. N., & Sim, M. R. (2018). Ergonomic interventions for preventing work-related musculoskeletal disorders of the upper limb and neck among office workers. Cochrane Database of Systematic Reviews, 2018(10). doi:10.1002/14651858.cd008570.pub3Hoe, V. C., Urquhart, D. M., Kelsall, H. L., & Sim, M. R. (2012). Ergonomic design and training for preventing work-related musculoskeletal disorders of the upper limb and neck in adults. Cochrane Database of Systematic Reviews. doi:10.1002/14651858.cd008570.pub2Van Eerd, D., Munhall, C., Irvin, E., Rempel, D., Brewer, S., van der Beek, A. J., … Amick, B. (2015). Effectiveness of workplace interventions in the prevention of upper extremity musculoskeletal disorders and symptoms: an update of the evidence. Occupational and Environmental Medicine, 73(1), 62-70. doi:10.1136/oemed-2015-102992Korunka, C., Dudak, E., Molnar, M., & Hoonakker, P. (2010). Predictors of a successful implementation of an ergonomic training program. Applied Ergonomics, 42(1), 98-105. doi:10.1016/j.apergo.2010.05.006Foxon, M. (1993). A process approach to the transfer of training. Australasian Journal of Educational Technology, 9(2). doi:10.14742/ajet.2104Stone, R. T., Watts, K. P., Zhong, P., & Wei, C.-S. (2011). Physical and Cognitive Effects of Virtual Reality Integrated Training. Human Factors: The Journal of the Human Factors and Ergonomics Society, 53(5), 558-572. doi:10.1177/0018720811413389Berg, L. P., & Vance, J. M. (2016). Industry use of virtual reality in product design and manufacturing: a survey. Virtual Reality, 21(1), 1-17. doi:10.1007/s10055-016-0293-9Mahmood, T., Scaffidi, M. A., Khan, R., & Grover, S. C. (2018). Virtual reality simulation in endoscopy training: Current evidence and future directions. World Journal of Gastroenterology, 24(48), 5439-5445. doi:10.3748/wjg.v24.i48.5439Wong, M. A. M. E., Chue, S., Jong, M., Benny, H. W. K., & Zary, N. (2018). Clinical instructors’ perceptions of virtual reality in health professionals’ cardiopulmonary resuscitation education. SAGE Open Medicine, 6, 205031211879960. doi:10.1177/2050312118799602Farra, S. L., Miller, E. T., & Hodgson, E. (2015). Virtual reality disaster training: Translation to practice. Nurse Education in Practice, 15(1), 53-57. doi:10.1016/j.nepr.2013.08.017Yin, C. W., Sien, N. Y., Ying, L. A., Chung, S. F.-C. M., & Tan May Leng, D. (2014). Virtual reality for upper extremity rehabilitation in early stroke: a pilot randomized controlled trial. Clinical Rehabilitation, 28(11), 1107-1114. doi:10.1177/0269215514532851Sacks, R., Perlman, A., & Barak, R. (2013). Construction safety training using immersive virtual reality. Construction Management and Economics, 31(9), 1005-1017. doi:10.1080/01446193.2013.828844Zhao, D., & Lucas, J. (2014). Virtual reality simulation for construction safety promotion. International Journal of Injury Control and Safety Promotion, 22(1), 57-67. doi:10.1080/17457300.2013.861853Li, X., Yi, W., Chi, H.-L., Wang, X., & Chan, A. P. C. (2018). A critical review of virtual and augmented reality (VR/AR) applications in construction safety. Automation in Construction, 86, 150-162. doi:10.1016/j.autcon.2017.11.003Chi, H.-L., Kang, S.-C., & Wang, X. (2013). Research trends and opportunities of augmented reality applications in architecture, engineering, and construction. Automation in Construction, 33, 116-122. doi:10.1016/j.autcon.2012.12.017Kaufman, R., & Keller, J. M. (1994). Levels of evaluation: Beyond Kirkpatrick. Human Resource Development Quarterly, 5(4), 371-380. doi:10.1002/hrdq.3920050408Bates, R. (2004). A critical analysis of evaluation practice: the Kirkpatrick model and the principle of beneficence. Evaluation and Program Planning, 27(3), 341-347. doi:10.1016/j.evalprogplan.2004.04.011Holton, E. F. (1996). The flawed four-level evaluation model. Human Resource Development Quarterly, 7(1), 5-21. doi:10.1002/hrdq.3920070103Axtell, C. M., Maitlis, S., & Yearta, S. K. (1997). Predicting immediate and longer‐term transfer of training. Personnel Review, 26(3), 201-213. doi:10.1108/00483489710161413Norman, G. (2010). Likert scales, levels of measurement and the «laws» of statistics. Advances in Health Sciences Education, 15(5), 625-632. doi:10.1007/s10459-010-9222-yTaber, K. S. (2017). The Use of Cronbach’s Alpha When Developing and Reporting Research Instruments in Science Education. Research in Science Education, 48(6), 1273-1296. doi:10.1007/s11165-016-9602-2HARRELL, W. A. (1990). PERCEIVED RISK OF OCCUPATIONAL INJURY: CONTROL OVER PACE OF WORK AND BLUE-COLLAR VERSUS WHITE-COLLAR WORK. Perceptual and Motor Skills, 70(3), 1351. doi:10.2466/pms.70.3.1351-1359Clark, R. E. (1983). Reconsidering Research on Learning from Media. Review of Educational Research, 53(4), 445-459. doi:10.3102/00346543053004445Metcalf, S., Chen, J., Kamarainen, A., Frumin, K., Vickrey, T., Grotzer, T., & Dede, C. (2014). Shifts in Student Motivation during Usage of a Multi-User Virtual Environment for Ecosystem Science. International Journal of Virtual and Personal Learning Environments, 5(4), 1-16. doi:10.4018/ijvple.201410010

Sistemas de pulido para restauraciones cerámicas. Revisión de la literatura

El pulido es un paso de suma importancia en el flujo de trabajo de las restauraciones cerámicas, después de realizado un ajuste con puntas o piedras diamantadas, ya que disminuye la rugosidad de las superficies tratadas. Esto repercute positivamente en las propiedades mecánicas y ópticas del material. Sin embargo, la poca literatura disponible acerca de este procedimiento hace que sea pasado por alto. Debido a esto, el presente articulo tuvo como objetivo realizar una revisión bibliográfica sobre los diferentes protocolos de pulido para las diversas restauraciones cerámicas de mayor uso: Feldespática, disilicato de litio y zirconia en sus diferentes presentaciones. Se describen aspectos relevantes sobre el pulido mecánico, la rugosidad superficial y los sistemas de pulido actuales para cerámicas