Design of a compressed air vehicle powertrain: The SG9C concept

These papers are intended to find out if an urban compressed air vehicle would be possible, so it could reduce the air pollution of cities and metropolises. To answer that has been designed a powertrain for an air powered vehicle. The main components of it and those which have required a deep study and analysis are the pneumatic engine and the compressed air tank. The engine selected for this project has been the 9 chamber Di Pietro engine, invented by Angelo Di Pietro. The air tank chosen has been a type IV CNG (Compressed Natural Gas) tank, which are already used in mobility applications. By the means of mathematical function extrapolation, vehicle dynamics simulations and other calculus referring to thermodynamics and fluids mechanics, among others, it has been demonstrated that an urban compressed air powered by the Di Pietro engine is capable enough to be a useful tool for city mobility and thus for fighting climate changeObjectius de Desenvolupament Sostenible::9 - Indústria, Innovació i InfraestructuraObjectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenible

Monte Carlo study of few-bosons in a one-dimensional trap

Treballs Finals de Grau de Física, Facultat de Física, Universitat de Barcelona, Curs: 2023, Tutors: Bruno Juliá-Díıaz, Grigori AstrakharchikWe consider a one-dimensional system of few-bosons in a harmonic trap that interact via a contact potential. In addition, we explore a system of non-interacting bosons in the presence of an impurity. The Variational Monte Carlo method is utilised to calculate an upper bound of the ground state energy. Furthermore, we numerically obtain the one-body density matrix, which allows us to determine the occupation numbers and the impurity density profile. The occupation numbers reveal that, in the absence of any impurity, the condensation diminishes as the repulsive interaction strength among bosons increases. Finally, in the presence of an impurity, we show the existence of two distinct regimes: a miscible regime and a non-miscible one

A Framework for Capacity and Operations Planning in Services Organizations Employing Workers with Intellectual Disabilities

[EN] This paper presents an integrated framework for capacity and operations planning in Spanish sheltered employment centers (SECs). Employment provides socio-economic opportunities for people with disability. Well functioning SECs that provide opportunities for people with and without disability to work alongside each other are an important component of Spain's current labor market. To be economically sustainable, SECs need to satisfy their clients expectations in terms of price, flexibility and performance, whilst taking into account and strengthening the diverse skills and abilities of their workforce like specific learning and forgetting processes. The SEC studied herein, a non-for-profit organization whose mission is to create employment for people with disabilities its workforce is deployed directly on clients' premises. Efficient management across this multi-site environment, whilst supporting the diverse employment needs of its staff, is of paramount importance. This paper contributes an integrated framework to support SEC capacity and operations planning, which prioritizes the explicit training needs of workers with disability at all levels (strategic, tactical, and operational) as a lever for achieving the organization's goals.García Sabater, JP.; Maheut, J.; Ruiz, A.; García Sabater, JJ. (2020). A Framework for Capacity and Operations Planning in Services Organizations Employing Workers with Intellectual Disabilities. Sustainability. 12(22):1-17. https://doi.org/10.3390/su12229713S1171222Fundación Espurnahttps://www.espurna.org/Convention on the Rights of Persons with Disabilities (A/RES/61/106)—Resolution adopted by the General Assembly on 13 December 2006https://www.un.org/en/development/desa/population/migration/generalassembly/docs/globalcompact/A_RES_61_106.pdfJarhag, S., Nilsson, G., & Werning, M. (2009). Disabled Persons and the Labor Market in Sweden. Social Work in Public Health, 24(3), 255-272. doi:10.1080/19371910802595315Mark, B. G., Hofmayer, S., Rauch, E., & Matt, D. T. (2019). Inclusion of Workers with Disabilities in Production 4.0: Legal Foundations in Europe and Potentials Through Worker Assistance Systems. Sustainability, 11(21), 5978. doi:10.3390/su11215978Santos, P. J. de los, & Costa, R. S. (2015). Workers with disabilities in sheltered employment centres: a training needs analysis. International Journal of Inclusive Education, 20(7), 756-769. doi:10.1080/13603116.2015.1111446Miralles, C., Marin-Garcia, J. A., Ferrus, G., & Costa, A. M. (2010). Operations research/management science tools for integrating people with disabilities into employment. A study on Valencia’s Sheltered Work Centres for Disabled. International Transactions in Operational Research, 17(4), 457-473. doi:10.1111/j.1475-3995.2009.00727.xChaves-Avila, R., & Savall-Morera, T. (2019). The Social Economy in a Context of Austerity Policies: The Tension Between Political Discourse and Implemented Policies in Spain. VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations, 30(3), 487-498. doi:10.1007/s11266-018-00075-3López-Penabad, M.-C., Maside-Sanfiz, J. M., Torrelles Manent, J., & Iglesias-Casal, A. (2020). Application of the DEA Double Bootstrap to Analyze Efficiency in Galician Sheltered Workshops. Sustainability, 12(16), 6625. doi:10.3390/su12166625Galeano Revert, A., García-Sabater, J. P., & Miralles Insa, C. (2018). Triple Bottom-line Business Model. Case study on the organic food retailing. WPOM-Working Papers on Operations Management, 9(1), 30. doi:10.4995/wpom.v9i1.9131Chi, C.-F., Dewi, R. S., Jang, Y., & Liu, H.-L. (2018). Workplace accommodation for workers with intellectual or psychiatric disabilities. International Journal of Industrial Ergonomics, 68, 1-7. doi:10.1016/j.ergon.2018.06.001Ellinger, A. E., Naidoo, J., Ellinger, A. D., Filips, K., & Herrin, G. D. (2020). Applying blue ocean strategy to hire and assimilate workers with disabilities into distribution centers. Business Horizons, 63(3), 339-350. doi:10.1016/j.bushor.2020.01.009Lindsay, S., Cagliostro, E., Albarico, M., Mortaji, N., & Karon, L. (2018). A Systematic Review of the Benefits of Hiring People with Disabilities. Journal of Occupational Rehabilitation, 28(4), 634-655. doi:10.1007/s10926-018-9756-zBitencourt, R. S., & de M. Guimarães, L. B. (2012). Inclusion of people with disabilities in the production system of a footwear industry. Work, 41, 4767-4774. doi:10.3233/wor-2012-0027-4767Hübner, A. H., Kuhn, H., & Sternbeck, M. G. (2013). Demand and supply chain planning in grocery retail: an operations planning framework. International Journal of Retail & Distribution Management, 41(7), 512-530. doi:10.1108/ijrdm-05-2013-0104Tuomikangas, N., & Kaipia, R. (2014). A coordination framework for sales and operations planning (S&OP): Synthesis from the literature. International Journal of Production Economics, 154, 243-262. doi:10.1016/j.ijpe.2014.04.026Li, Y., Chen, J., & Cai, X. (2007). An integrated staff-sizing approach considering feasibility of scheduling decision. Annals of Operations Research, 155(1), 361-390. doi:10.1007/s10479-007-0215-zZeng, L., Zhao, M., & Liu, Y. (2017). Airport ground workforce planning with hierarchical skills: a new formulation and branch-and-price approach. Annals of Operations Research, 275(1), 245-258. doi:10.1007/s10479-017-2624-yLlort, N., Lusa, A., Martínez-Costa, C., & Mateo, M. (2018). A decision support system and a mathematical model for strategic workforce planning in consultancies. Flexible Services and Manufacturing Journal, 31(2), 497-523. doi:10.1007/s10696-018-9321-2Van den Bergh, J., Beliën, J., De Bruecker, P., Demeulemeester, E., & De Boeck, L. (2013). Personnel scheduling: A literature review. European Journal of Operational Research, 226(3), 367-385. doi:10.1016/j.ejor.2012.11.029Henderson, J. C., Krajewski, L. J., & Showalter, M. J. (1982). An integrated approach for manpower planning in the service sector. Omega, 10(1), 61-73. doi:10.1016/0305-0483(82)90086-xKomarudin, De Feyter, T., Guerry, M.-A., & Vanden Berghe, G. (2020). The extended roster quality staffing problem: addressing roster quality variation within a staffing planning period. Journal of Scheduling, 23(2), 253-264. doi:10.1007/s10951-020-00654-7Das, D., & Yadav, C. (2020). A framework of hiring strategy for manpower hiring in a hyper-local food delivery organization. Journal of Advances in Management Research, 18(1), 113-135. doi:10.1108/jamr-06-2020-0104Maenhout, B., & Vanhoucke, M. (2013). An integrated nurse staffing and scheduling analysis for longer-term nursing staff allocation problems. Omega, 41(2), 485-499. doi:10.1016/j.omega.2012.01.002Benavides, A. J., Ritt, M., & Miralles, C. (2014). Flow shop scheduling with heterogeneous workers. European Journal of Operational Research, 237(2), 713-720. doi:10.1016/j.ejor.2014.02.012Miralles, C., García-Sabater, J. P., Andrés, C., & Cardós, M. (2008). Branch and bound procedures for solving the Assembly Line Worker Assignment and Balancing Problem: Application to Sheltered Work centres for Disabled. Discrete Applied Mathematics, 156(3), 352-367. doi:10.1016/j.dam.2005.12.012Moreira, M. C. O., Pastor, R., Costa, A. M., & Miralles, C. (2017). The multi-objective assembly line worker integration and balancing problem of type-2. Computers & Operations Research, 82, 114-125. doi:10.1016/j.cor.2017.01.003Bartlo, P., & Klein, P. J. (2011). Physical Activity Benefits and Needs in Adults With Intellectual Disabilities: Systematic Review of the Literature. American Journal on Intellectual and Developmental Disabilities, 116(3), 220-232. doi:10.1352/1944-7558-116.3.220Verdugo, M. A., Jordán de Urríes, F. B., Jenaro, C., Caballo, C., & Crespo, M. (2006). Quality of Life of Workers with an Intellectual Disability in Supported Employment. Journal of Applied Research in Intellectual Disabilities, 19(4), 309-316. doi:10.1111/j.1468-3148.2006.00277.xBossink, L. W. M., van der Putten, A. A., & Vlaskamp, C. (2017). Understanding low levels of physical activity in people with intellectual disabilities: A systematic review to identify barriers and facilitators. Research in Developmental Disabilities, 68, 95-110. doi:10.1016/j.ridd.2017.06.008Milner, A., LaMontagne, A. D., Aitken, Z., Bentley, R., & Kavanagh, A. M. (2014). Employment status and mental health among persons with and without a disability: evidence from an Australian cohort study. Journal of Epidemiology and Community Health, 68(11), 1064-1071. doi:10.1136/jech-2014-204147Nembhard, D. A., & Uzumeri, M. V. (2000). Experiential learning and forgetting for manual and cognitive tasks. International Journal of Industrial Ergonomics, 25(4), 315-326. doi:10.1016/s0169-8141(99)00021-9Siporin, S., & Lysack, C. (2004). Quality of Life and Supported Employment: A Case Study of Three Women With Developmental Disabilities. The American Journal of Occupational Therapy, 58(4), 455-465. doi:10.5014/ajot.58.4.455Buntinx, W. H. E., & Schalock, R. L. (2010). Models of Disability, Quality of Life, and Individualized Supports: Implications for Professional Practice in Intellectual Disability. Journal of Policy and Practice in Intellectual Disabilities, 7(4), 283-294. doi:10.1111/j.1741-1130.2010.00278.xQin, R., & Nembhard, D. A. (2015). Workforce agility in operations management. Surveys in Operations Research and Management Science, 20(2), 55-69. doi:10.1016/j.sorms.2015.11.001Rius-Sorolla, G., Maheut, J., Estellés-Miguel, S., & Garcia-Sabater, J. P. (2018). Coordination mechanisms with mathematical programming models for decentralized decision-making: a literature review. Central European Journal of Operations Research, 28(1), 61-104. doi:10.1007/s10100-018-0594-

Hybrid approach of discrete event simulation integrated with location search algorithm in a cells assignment problem: a case study

[EN] This paper presents a case study describing a cell assignment problem in an assembly facility. These cells receive parts from external suppliers, and sort and sequence these parts to feed the final assembly line. Therefore, to each cell are associated important inbound and outbound flows generating hundreds of material handling equipment movements along the facility, impacting the traffic density and causing eventually safety issues in the plant. Following an important plant redesign, cells have been relocated, and the plant managers need to decide how to manage the new logistic flows. To that aim, a hybrid approach encompassing mathematical optimization and discrete event simulation (DES) is proposed. This approach allows us to reduce complexity by decomposing the design into two phases. The first phase deals with the problem of generating cell¿s assignment alternatives by using a heuristic method to find good quality solutions. Then, a DES software is used to dynamically evaluate the performance of the solutions with respect to operational features such as traffic congestion and intensity. This second phase provides interesting managerial insights on the manufacturing system from both quantitative and qualitative aspects related to in-plant safety and traffic.Saez-Mas, A.; García Sabater, JJ.; García Sabater, JP.; Maheut, J. (2020). Hybrid approach of discrete event simulation integrated with location search algorithm in a cells assignment problem: a case study. Central European Journal of Operations Research. 28(1):125-142. https://doi.org/10.1007/s10100-018-0548-5S125142281Anjos MF, Vieira MVC (2017) Mathematical optimization approaches for facility layout problems: the state-of-the-art and future research directions. Eur J Oper Res 261(1):1–16. https://doi.org/10.1016/j.ejor.2017.01.049Battini D, Boysen N, Emde S (2013) Just-in-time supermarkets for part supply in the automobile industry. J Manag Control 24(2):209–217. https://doi.org/10.1007/s00187-012-0154-yBenjaafar S (2002) Modeling and analysis of congestion in the design of facility layouts. Manag Sci 48(5):679–704. https://doi.org/10.1287/mnsc.48.5.679.7800Board TR (2010) Highway capacity manual. Environmental ProtectionBoysen N, Emde S, Hoeck M, Kauderer M (2015) Part logistics in the automotive industry: decision problems, literature review and research agenda. Eur J Oper Res 242(1):107–120. https://doi.org/10.1016/j.ejor.2014.09.065Caputo AC, Pelagagge PM, Salini P (2015) Modeling errors in kitting processes for assembly lines feeding. IFAC Proc Vol (IFAC PapersOnline) 48(3):338–344. https://doi.org/10.1016/j.ifacol.2015.06.104Centobelli P, Cerchione R, Murino T (2016) Layout and material flow optimization in digital factory. Int J Simul Model 15(2):223–235. https://doi.org/10.2507/IJSIMM15(2)3.327Dehghanimohammadabadi M, Keyser TK (2017) Intelligent simulation: integration of SIMIO and MATLAB to deploy decision support systems to simulation environment. Simul Model Pract Theory 71:45–60. https://doi.org/10.1016/j.simpat.2016.08.007Ficko M, Palcic I (2013) Designing a layout using the modified triangle method, and genetic algorithms. Int J Simul Model 12(4):237–251. https://doi.org/10.2507/IJSIMM12(4)3.244Gamberi M, Manzini R, Regattieri A (2009) An new approach for the automatic analysis and control of material handling systems: integrated layout flow analysis (ILFA). Int J Adv Manuf Technol 41(1–2):156–167. https://doi.org/10.1007/s00170-008-1466-9Gould O, Colwill J (2015) A framework for material flow assessment in manufacturing systems. J Ind Prod Eng 32(1):55–66. https://doi.org/10.1080/21681015.2014.1000403Hasda RK, Bhattacharjya RK, Bennis F (2016) Modified genetic algorithms for solving facility layout problems. Int J Interact Des Manuf (IJIDeM) 11(3):1–13. https://doi.org/10.1007/s12008-016-0362-zImran M, Kang C, Hae Lee Y, Zaib J, Aziz H (2017) Cell formation in a cellular manufacturing system using simulation integrated hybrid genetic algorithm. Comput Ind Eng 105:123–135. https://doi.org/10.1016/j.cie.2016.12.028Iqbal M, Hashmi MSJ (2001) Design and analysis of a virtual factory layout. J Mater Process Technol 118(1–3):403–410. https://doi.org/10.1016/S0924-0136(01)00908-6Jainury SM, Ramli R, Ab Rahman MN, Omar A (2014) Integrated Set Parts Supply system in a mixed-model assembly line. Comput Ind Eng 75(1):266–273. https://doi.org/10.1016/j.cie.2014.07.008Kanduc T, Rodic B (2016) Optimisation of machine layout using a force generated graph algorithm and simulated annealing. Int J Simul Model 15(2):275–287. https://doi.org/10.2507/IJSIMM15(2)7.335Kang J (2001) A new trend of parts supply system in Korean automobile industry; the case of the modular production system at Hyundai Motor Company. In: Proceedings of the fifth Russian-Korean international symposium on science and technology, 2001. KORUS '01. IEEE, Tomsk, Russia, Russia. https://doi.org/10.1109/KORUS.2001.975268Kim J, Yu G, Jang YJ (2016) Semiconductor FAB layout design analysis with 300-mm FAB data: “is minimum distance-based layout design best for semiconductor FAB design?”. Comput Ind Eng 99:330–346. https://doi.org/10.1016/j.cie.2016.02.012Krishnan KK, Jithavech I, Liao H (2009) Mitigation of risk in facility layout design for single and multi-period problems. Int J Prod Res 47(21):5911–5940. https://doi.org/10.1080/00207540802175337Ku M-Y, Hu MH, Wang M-J (2011) Simulated annealing based parallel genetic algorithm for facility layout problem. Int J Prod Res 49(6):1801–1812. https://doi.org/10.1080/00207541003645789Kulturel-Konak S (2017) A matheuristic approach for solving the dynamic facility layout a matheuristic approach for problem solving the dynamic facility layout problem. Proc Comput Sci 108(June):1374–1383. https://doi.org/10.1016/j.procs.2017.05.234Leveson N (2004) A new accident model for engineering safer systems. Saf Sci 42(4):237–270. https://doi.org/10.1016/S0925-7535(03)00047-XNegahban A, Smith JS (2014) Simulation for manufacturing system design and operation: literature review and analysis. J Manuf Syst 33(2):241–261. https://doi.org/10.1016/j.jmsy.2013.12.007Prajapat N, Tiwari A (2017) A review of assembly optimisation applications using discrete event simulation. Int J Comput Integr Manuf 30(2–3):215–228. https://doi.org/10.1080/0951192X.2016.1145812Saez-Mas A, Garcia-Sabater JP, Morant-Llorca J (2018) Using 4-layer architecture to simulate product and information flows in manufacturing. Int J Simul Model 17(1):30–41. https://doi.org/10.2507/IJSIMM17(1)408Seebacher G, Winkler H, Oberegger B (2015) In-plant logistics efficiency valuation using discrete event simulation. Int J Simul Model 14:60–70. https://doi.org/10.2507/IJSIMM14(1)6.289Singh RR, Sharma SPK (2006) A review of different approaches to the facility layout problems. Int J Adv Manuf Technol 30(5–6):425–433. https://doi.org/10.1007/s00170-005-0087-9Tompkins J, White J, Bozer Y, Tanchoco J (2003) Facilities planning. Wiley, New YorkTugnoli A, Khan F, Amyotte P, Cozzani V (2008) Safety assessment in plant layout design using indexing approach: implementing inherent safety perspective. Part 1—guideword applicability and method description. J Hazard Mater 160(1):100–109. https://doi.org/10.1016/j.jhazmat.2008.02.089Zhang M, Batta R, Nagi R (2009) Modeling of workflow congestion and optimization of flow routing in a manufacturing/warehouse facility. Manag Sci 55(2):267–280. https://doi.org/10.1287/mnsc.1080.0916Zhou F, AbouRizk SM, AL-Battaineh H (2009) Optimisation of construction site layout using a hybrid simulation-based system. Simul Model Pract Theory 17(2):348–363. https://doi.org/10.1016/j.simpat.2008.09.011Zhuo L, Chua Kim Huat D, Wee KH (2012) Scheduling dynamic block assembly in shipbuilding through hybrid simulation and spatial optimisation. Int J Prod Res 50(20):5986–6004. https://doi.org/10.1080/00207543.2011.639816Zupan H, Herakovic N, Starbek M (2016) hybrid algorithm based on priority rules for simulation of workshop production. Int J Simul Model 15(1):29–41. https://doi.org/10.2507/IJSIMM15(1)3.31

A Simple Computational Model for Acceptance/Rejection of Binary Sequence Generators

A simple binary model to compute the degree of balancedness in the output sequence of LFSR-combinational generators has been developed. The computational method is based exclusively on the handling of binary strings by means of logic operations. The proposed model can serve as a deterministic alternative to existing probabilistic methods for checking balancedness in binary sequence generators. The procedure here described can be devised as a first selective criterium for acceptance/rejection of this type of generators.Comment: 16 pages, 0 figure

Coproducción: Una revisión de la literatura

[ES] El objetivo del presente artículo es analizar la literatura existente en el entorno de la coproducción. De acuerdo con Deuermeyer y Pierskalla (1978), es posible afirmar que existe coproducción cuando un proceso productivo da como resultado más de un producto de manera simultánea. La coproducción aparece en ambientes de alta y baja tecnología de producción. La coproducción, suele ocurrir en entornos de producción en los que algunos procesos no se conocen/comprenden perfectamente y/o no están totalmente bajo control (coproducción incontrolada). Sin embargo, tal y como, se ha podido constatar en la realidad industrial, en ocasiones el proceso de coproducción, si se conoce/comprende perfectamente (coproducción controlada). La coproducción puede ser un fenómeno intrínseco al propio proceso productivo (coproducción no deliberada). Aunque en ocasiones puede ser escogida por el gestor del proceso (coproducción deliberada). Así, resulta interesante clasificar la literatura respecto a estas variables, pues hasta la fecha no se había realizado, proporcionando al lector una visión clara de la literatura existente en torno a la coproducción.Este trabajo ha sido realizado gracias a la financiación del Ministerio de Ciencia e Innovación a través del proyecto CORSARI MAGIC: Coordinación de operaciones en redes de suministro/demanda ajustadas, resilientes a la incertidumbre: modelos y algoritmos para la gestión de la incertidumbre y la complejidad, DPI: 2010-18243.Vidal Carreras, PI. (2011). Coproducción: Una revisión de la literatura. Working Papers on Operations Management. 2(1):11-17. doi:10.4995/wpom.v2i1.810SWORD111721BITRAN, G. B., & LEONG, T.-Y. (1995). Co-production of substitutable products. Production Planning & Control, 6(1), 13-25. doi:10.1080/09537289508930249Bitran, G. R., & Dasu, S. (1992). Ordering Policies in an environment of Stochastic Yields and Substitutable Demands. Operations Research, 40(5), 999-1017. doi:10.1287/opre.40.5.999Bitran, G. R., & Gilbert, S. M. (1994). Co-Production Processes with Random Yields in the Semiconductor Industry. Operations Research, 42(3), 476-491. doi:10.1287/opre.42.3.476Bitran, G. R., & Leong, T.-Y. (1992). Deterministic Approximations to Co-Production Problems with Service Constraints and Random Yields. Management Science, 38(5), 724-742. doi:10.1287/mnsc.38.5.724Bitran, G. R., & Yanasse, H. H. (1984). Deterministic Approximations to Stochastic Production Problems. Operations Research, 32(5), 999-1018. doi:10.1287/opre.32.5.999Bravo, D., Rodríguez, E., & Medina, M. (2009). Nisin and lacticin 481 coproduction by Lactococcus lactis strains isolated from raw ewes’ milk. Journal of Dairy Science, 92(10), 4805-4811. doi:10.3168/jds.2009-2237Deuermeyer, B. L. (1979). A Multi-Type Production System for Perishable Inventories. Operations Research, 27(5), 935-943. doi:10.1287/opre.27.5.935Deuermeyer, B. L., & Pierskalla, W. P. (1978). A By-Product Production System with an Alternative. Management Science, 24(13), 1373-1383. doi:10.1287/mnsc.24.13.1373DUENYAS, I., & TSAI, C.-Y. (2000). Control of a manufacturing system with random product yield and downward substitutability. IIE Transactions, 32(9), 785-795. doi:10.1080/07408170008967438Evans, R. V. (1969). Inventory control of by-products. Naval Research Logistics Quarterly, 16(1), 85-92. doi:10.1002/nav.3800160107Garcia-Sabater, J. P.; Vidal-Carreras, P. I. (2010). Programación de producción en los proveedores del automóvil. Revista Virtual Pro, Vol. 104, p. 23.García-Sabater, J. P., Vidal-Carreras, P.I., & García-Sabater, J. J. (2005). Estudio de la Problemática de Programación de la Producción en el sector del Automóvil. Aplicación a una red de fabricación, in VIII Congreso de Ingeniería de Organización.Gerchak, Y., & Grosfeld-Nir, A. (1999). International Journal of Flexible Manufacturing Systems, 11(4), 371-377. doi:10.1023/a:1008131213614GERCHAK, Y., TRIPATHY, A., & WANG, K. (1996). Co-production models with random functionality yields. IIE Transactions, 28(5), 391-403. doi:10.1080/07408179608966286Grosfeld-Nir, A., & Gerchak, Y. (2004). Multiple Lotsizing in Production to Order with Random Yields: Review of Recent Advances. Annals of Operations Research, 126(1-4), 43-69. doi:10.1023/b:anor.0000012275.01260.f5LISBONA, P., & ROMEO, L. (2008). Enhanced coal gasification heated by unmixed combustion integrated with an hybrid system of SOFC/GT. International Journal of Hydrogen Energy, 33(20), 5755-5764. doi:10.1016/j.ijhydene.2008.06.031Mcgillivray, R., & Silver, E. (1978). Some Concepts For Inventory Control Under Substitutable Demand*. INFOR: Information Systems and Operational Research, 16(1), 47-63. doi:10.1080/03155986.1978.11731687Nahmias, S., & Moinzadeh, K. (1997). Lot Sizing with Randomly Graded Yields. Operations Research, 45(6), 974-989. doi:10.1287/opre.45.6.974Nielsen, D. R., Yoon, S.-H., Yuan, C. J., & Prather, K. L. J. (2010). Metabolic engineering of acetoin and meso-2, 3-butanediol biosynthesis in E. coli. Biotechnology Journal, 5(3), 274-284. doi:10.1002/biot.200900279Öner, S., & Bilgiç, T. (2008). Economic lot scheduling with uncontrolled co-production. European Journal of Operational Research, 188(3), 793-810. doi:10.1016/j.ejor.2007.05.016Ou, J., & Wein, L. M. (1995). Dynamic Scheduling of a Production/Inventory System with By-Products and Random Yield. Management Science, 41(6), 1000-1017. doi:10.1287/mnsc.41.6.1000Caner Taşkın, Z., & Tamer Ünal, A. (2009). Tactical level planning in float glass manufacturing with co-production, random yields and substitutable products. European Journal of Operational Research, 199(1), 252-261. doi:10.1016/j.ejor.2008.11.024Tomlin, B., & Wang, Y. (2008). Pricing and Operational Recourse in Coproduction Systems. Management Science, 54(3), 522-537. doi:10.1287/mnsc.1070.0807Vidal-Carreras, P. I., & Garcia-Sabater, J. P. (2009). Comparison of heuristics for an economic lot scheduling problem with deliberated coproduction. Journal of Industrial Engineering and Management, 2(3). doi:10.3926/jiem.2009.v2n3.p437-463Yano, C. A., & Lee, H. L. (1995). Lot Sizing with Random Yields: A Review. Operations Research, 43(2), 311-334. doi:10.1287/opre.43.2.31

Operations Management at the service of health care management: Example of a proposal for action research to plan and schedule health resources in scenarios derived from the COVID-19 outbreak

[EN] With this work, we intend to promote research on the application of Operations Management tools in order to assist with decision-making in health crisis situations. During the first six weeks of the COVID-19 crisis in Spain, we have contacted a large number of hospital and health department managers in the Valencian Community and other regions of Spain. The result is that very few, at least when contact was made and at the time of writing this article, had consulted staff members in the Operations Management area for advice on this situation, and they are quite reluctant to do so. This is in spite of the fact that some medical sources also consider this crisis to be one of resources, not merely a medical crisis. Our opinion is that Operations Management can make a useful and valuable contribution to anticipate and improve the management of scarce resources, even in times of crisis. If those responsible for public health or heads of hospitals do not see this usefulness, then there is a huge gap between research and practice in Operations Management and what is transmitted to the healthcare sector. Our aim is to help reduce this gap.Marin-Garcia, JA.; García Sabater, JP.; Ruiz, A.; Maheut, J.; García Sabater, JJ. (2020). Operations Management at the service of health care management: Example of a proposal for action research to plan and schedule health resources in scenarios derived from the COVID-19 outbreak. Journal of Industrial Engineering and Management. 13(2):213-227. https://doi.org/10.3926/jiem.3190S21322713

La creación de un contexto virtual para el aprendizaje de lenguas extranjeras mediante "hangouts"

La enseñanza de idiomas cuenta hoy con instrumentos versátiles y de alcance global proporcionados por las nuevas tecnologías de comunicación que, al combinarse con profesionales de la enseñanza de lenguas, produce óptimos resultados. La investigación que aquí se presenta es producto de una iniciativa aplicada al aprendizaje de español por anglófonos de los EEUU en ámbito universitario. El objetivo es crear un contexto virtual de aprendizaje en el que puedan interactuar alumnos de Rice University y profesores de la Universidad de Sevilla. Para ello se eligió la herramienta Hangouts de Google. La metodología se basa en el análisis cuantitativo y cualitativo de los procesos de aprendizaje de los alumnos, utilizando el sistema de medición OPIc. Los logros obtenidos con las tutorías virtuales son significativamente positivos, pues estas clases permiten a los estudiantes ganar conocimientos así como fomentar la comunicación entre culturas, aclarar dudas, hacer preguntas a otro instructor, practicar las habilidades de conversación y desarrollar fluidez en un entorno relajado.Modern communication technologies provide versatile and global-reaching tools that enhance the teaching of foreign languages today which combine with professional language instructors produces optimal results. The research shown here is the consequence of a project based on the teaching of Spanish to Anglophones in a university in the U.S.A. The objective was to create a virtual learning environment where students from Rice University and instructors from the University of Seville could interact in an academic setting. To accomplish this, Google’s Hangouts was the chosen tool for this innovative teaching strategy. The methodology used was based on the qualitative and quantitative analysis of the students’ learning processes using the OPIc as the measuring tool. The results obtained using Hangouts for virtual tutorials are significantly positive since they allow the students to gain knowledge, as well as to heighten the interaction between cultures, clarify doubts, practice conversation, and to develop fluidity in a comfortable setting

La mejora de la empleabilidad de los discapacitados a través de los Centros de Ocupación laboral. Aportaciones de la Ingeniería de Organización Industrial.

El objetivo de este articulo es presentar un proyecto de investigación que pretende extender los beneficios de las técnicas de Ingeniería de Métodos a los entornos relacionados con los Centros Ocupacionales y Centros Especiales de Empleo de discapacitad