Alex J. Ruiz-Torres

Journal Publications

Ruiz-Torres, A.J., J. H. Ablanedo-Rosas, F. Mahmoodi, and S. Ohmori (2023) ‘Determining number of suppliers, duration of supply cycle and allocation to in-house production under supply uncertainty’, Computers and Industrial Engineering, 182.

Ohmori, S., A. J. Ruiz-Torres, and F. Mahmoodi (2023) ‘Multi-Echelon Inventory Optimization under Disruption Risk’, Operations and Supply Chain Management: An International Journal, 12 (2), 177-189.

Hlali, A., J. H. Ablanedo-Rosas, and A. J. Ruiz-Torres. (2023), ‘Operational efficiency of major cargo seaports in some developing regions: Results from a bootstrap DEA’, International Journal of Shipping and Transport Logistics, 16 (3/4), 290-319.

Mar-Ortiz J., B. Adenso-Diaz, and A. J. Ruiz-Torres. (2022), ‘Scheduling in parallel machines with two objectives: analysis of factors that influence the Pareto frontier’. Operational Research, 22, 4585-4605.

Ruiz-Torres, A. J., F. Mahmoodi, S. Ohmori, & A. Hlali. (2022). ‘Suppliers portfolio and returner incentive decisions in closed-loop remanufacturing systems under multiple stochastic scenarios’, International Journal of Sustainable Engineering, 15(1), 210-227.

Ruiz-Torres, A. J., G. Paletta, and B. Adenso-Diaz. (2022), ‘Hybrid two stage flowshop scheduling with secondary resources based on time buckets’, International Journal of Production Research, 60(2), 1954-1972.

Ablanedo-Rosas, J. H., I. J. Rubio, J. Chen, and A. J. Ruiz-Torres. (2021), ‘COVID-19 impact on the operational efficiency of a downtown hotel’. Anatolia, 34(2), 130-143.

Mar-Ortiz J., B. Adenso-Diaz, and A. J. Ruiz-Torres. (2022), ‘Scheduling in parallel machines with two objectives: analysis of factors that influence the Pareto frontier’. Operational Research, 22, 4585-4605.

Ruiz-Torres, A. J., F. Mahmoodi, S. Ohmori, & A. Hlali. (2022). ‘Suppliers portfolio and returner incentive decisions in closed-loop remanufacturing systems under multiple stochastic scenarios’, International Journal of Sustainable Engineering, 15(1), 210-227.

Ruiz-Torres, A. J., G. Paletta, and B. Adenso-Diaz. (2022), ‘Hybrid two stage flowshop scheduling with secondary resources based on time buckets’, International Journal of Production Research, 60(2), 1954-1972.

Ohmori, S., Arakane, T., Ruiz-Torres, A., and Yoshimoto, K. (2021), ‘The Multiple Supply Chain Design Problem: Integration of Multiple Configurations Based on Product, Customer, and Supply Chain Characteristics’. International Journal of Information Systems and Supply Chain Management, 14(3), 39-62.

Ruiz-Torres, A. J., J. Ablanedo-Rosas, and D. Jurburg. (2021), ‘Flowshop scheduling with machine deterioration based on job sequences’. Ingenieria y Competitividad, 23(2).

Ruiz-Torres, A. J., D. Jurburg, and Y. Lopez-Correa. (2020), ‘Modelo de decisión para determinar fuentes de retorno, incentivos y capacidad en un sistema de remanufactura’. Memoria Investigaciones en Ingeniería, 19, 2-24.

Ho, J. I Massabo., G. Paletta, and A. J. Ruiz-Torres. (2019), ‘A note on posterior tight worst-case bounds for Longest Processing Time schedules’. 4OR: A Quarterly Journal of Operations Research, 17(1), 97-107.

Ruiz-Torres, A. J., F. Mahmoodi, and S. Ohmori. (2019), ‘Joint determination of supplier capacity and returner incentives in a closed-loop supply chain’. Journal of Cleaner Production, 215, 1351-1361.

Ruiz-Torres, A. J., J. Ablanedo-Rosas, S. Mukhopadhyay, and G. Paletta. (2019), ‘Scheduling workers: a multi-criteria model considering their satisfaction’. Computers & Industrial Engineering, 128, 747-754.

Ruiz-Torres, A. J., G. Cardoza, M. Kuula, Y. Oliver, and H. Rosa-Polanco. (2018), ‘Logistic services in the Caribbean region: an analysis of collaboration, innovation capabilities and process improvement’. Academia - Revista Latinoamericana de Administración, 31 (3), 534-552.

Ruiz-Torres, A. J., C. Villafañe-Rodríguez, and J. A. Peña-Hevia. (2018), ‘Caracterización de 37 revistas académicas en las ciencias administrativas publicadas en Latinoamérica’. Revista Pensamiento & Gestion. 44, 133-155.

Pérez, E., R. Ambati, and A. J. Ruiz-Torres. (2018), ‘Maximizing the number of on-time jobs on parallel servers with sequence dependent deteriorating processing times and periodic maintenance’. International Journal of Operational Research, 32(3), 267-289.

Ruiz-Torres, A., G. Paletta, F. Mahmoodi, and J. Ablanedo-Rosas. (2018), ‘Scheduling assemble-to-order systems with multiple cells to minimize costs and tardy deliveries’. Computers & Industrial Engineering, 115, 290-303.

Kuula, M., M. Malik, P. Raitasuo, and A. J. Ruiz-Torres. (2017) ‘The effect of long-term customer relationships and customer-related business uncertainty on the performance of logistic service providers’. International Journal of Integrated Supply Management, 11(2/3), 172-192.

Ruiz-Torres, A. J., F. Mahmoodi, and M. Kuula. (2017), ‘Quality assurance laboratory planning system to maximize worker preference subject to certification and preference balance constraints’. Computers & Operations Research, 83, 140-149.

Ruiz-Torres, A. J., G. Paletta, and M. Rym. (2017), ‘Makespan minimization with sequence dependent machine deterioration and maintenance events’. International Journal of Production Research, 55(2), 462-479.

Lopez, F., J. Ho, and A. J. Ruiz-Torres. (2016), ‘A computational analysis of the impact of correlation and data translation on DEA efficiency scores’. Journal of Industrial and Production Engineering, 33(3), 192-204.

Paletta, G., Massabo, I., and A. J. Ruiz-Torres. (2016), ‘A note on LPT Schedule for two uniform machines’. Journal of Scheduling, 19(2), 207-211.

Ruiz-Torres, A. J., J. Ayala-Cruz, J., N. Alomoto, and J. L Acero-Chavez. (2015), ‘Revisión de la literatura sobre gestión de la calidad: caso de las revistas publicadas en Hispanoamérica y Espana’. Estudios Gerenciales, 31, 319-334.

Paletta, G., and A.J. Ruiz-Torres. (2015), ‘Partial solutions and Multifit algorithm for multiprocessor scheduling’. Journal of Mathematical Modelling and Algorithms in Operations Research, 14 (2), 125-143.

Ruiz-Torres, Paletta, G., and E. Perez-Roman. (2015), ‘Maximizing the percentage of on-time jobs with sequence dependent deteriorating process times’. International Journal of Operations Research and Information Systems, 6 (3), 1-18.

Ruiz-Torres, A. J., Alomoto, N., Paletta, G., and E. Perez-Roman. (2015), ‘Scheduling to maximize worker satisfaction and on time orders’. International Journal of Production Research, 53 (9), 2836-2852.

Castro-Gonzáles, S., J. Peña-Vinces, A. J. Ruiz-Torres, and J. C. Sosa. (2014), ‘Estudio intrapaíses de la competitividad global desde el enfoque del doble diamante para Puerto Rico, Costa Rica y Singapur’. Investigaciones Europeas de Dirección y Economía de la Empresa, 20(3), 122-130.

Ruiz-Torres, A. J., J. Ablanedo-Rosas, N. Alomoto, F. Mahmoodi, and A. Zeng. (2014), ‘Production planning of parallel resources considering yields, failures and production costs’. International Journal of Applied Management Science, 6(2), 99-117.

Alomoto, N., C. Acuña, M. Salvador, J. Ortiz, J. and A.J. Ruiz-Torres. (2014), ‘La gestión de la cadena de suministro: caso de las pymes en Ecuador’, Revista Formación Gerencial, 10(2), 148-175.

Ruiz-Torres, A. J., J. Ablanedo-Rosas, N. Alomoto and D. Jadan-Aviles (2014), ‘Minimización de la tardanza en problemas de programación de tareas en maquinas paralelas con deterioro de los recursos’. Revista Ingeniería Industrial (Universidad del Bío- Bío, Chile), 13 (1), 51-75.

Ruiz-Torres, A.J., F. Mahmoodi, and A. Zeng. (2013), ‘Supplier selection model with contingency planning for supplier failures’. Computers & Industrial Engineering, 66, 374-382.

Ruiz-Torres, A. J., A. Mendoza, and J. Ablanedo-Rosas. (2013), ‘Modelo para la planificación en la cadena de suministro: Selección y asignación a proveedores en el caso de lotes fijos’. Ingenieria y Desarollo, 30(1), 1-21.

Cossari, A., Ho, J. C., Paletta, G., and A. J. Ruiz-Torres. (2013), ‘Minimizing workload balancing criteria on identical parallel machines’. Journal of Industrial and Production Engineering, 30(3), 160-172.

Ruiz-Torres, A. J., Paletta, G., and E. Perez-Roman. (2013), ‘Parallel machine scheduling to minimize the makespan with sequence dependent deteriorating effects’. Computers & Operations Research, 40, 2051-2061.

Ruiz-Torres, A. J., J. Ablanedo-Rosas, and S. Mukhopadhyay. (2013), ‘Supplier allocation model for textile recycling Operations’. International Journal of Logistics Systems and Management, 15(1), 108-124.

Otero, L. D., G. Centeno, C. E. Otero, and A. J. Ruiz-Torres. (2012), ‘A fuzzy goal programming model for skill-based personnel assignments’. International Journal of Multi-criteria Decision Making, 2(4), 313-337.

Ruiz-Tores, A. J., S. Penkova, and C. Villafañe-Rodríguez, (2012), ‘Evaluación y clasificación de revistas arbitradas en el área de administración de empresas Publicadas en Español’. Academia Revista Latinoamericana de Administración, 51, 48-64.

Ruiz-Torres, A.J., F. Mahmoodi, and J. Ayala-Cruz. (2012), ‘Supply chain management research in Latin America: a review’. Supply Chain Forum: an International Journal, 13(1), 20-36.

Ruiz-Torres, A. J., J. Ablanedo-Rosas, and J. Ayala-Cruz. (2012), ‘Modelo de asignación de compras a proveedores considerando su flexibilidad y probabilidad de incumplimiento en la entrega’, Revista Estudios Gerenciales, 28 (122), 29-48.

Ruiz-Torres, A. J., J. Ablanedo-Rosas, and D. Otero. (2012), ‘Scheduling with multiple tasks per job – the case of quality control laboratories in the pharmaceutical industry’, International Journal of Production Research, 50 (3), 691-705.

Ruiz-Torres, A.J., R. Villalobos, M. Salvador, and N. Alomoto. (2012), ‘Planning models for floriculture operations’. International Journal of Applied Management Science, 4(2), 148-163.

Ruiz-Torres, A. J., J. Ablanedo-Rosas, and J. Ho. (2012), ‘The parallel machine scheduling problem with variable demand and a pre-defined lot size’. International Journal of Operational Research, 14 (1), 1- 30.

Cossari, A., Ho, J. C., Paletta, G., and A. J. Ruiz-Torres. (2012), ‘A new heuristic for workload balancing on identical parallel machines and a statistical perspective on the workload balancing criteria’. Computers & Operations Research, 39, 1382-1393.

Ruiz-Torres, A.J., N. Alomoto, A. Collazo, G. Molinary, E. Nieves, E. Suarez-Bernier. (2011), ‘Decisiones operacionales de la cadena de suministro: un modelo para la subcontratación’, Revista Formación Gerencial, 10(2), 148-175.

Ho, J.C., F. Lopez, B., A. J. Ruiz-Torres, and B., Tseng. (2011), ‘Minimizing total weighted flowtime subject to minimum makespan on two identical parallel machines’. Journal of Intelligent Manufacturing, 22, 179-190.

Ruiz-Torres, A. J., J. Ho and J. Ablanedo-Rosas. (2011), 'Makespan and workstation utilization minimization in a flowshop with operations flexibility’. OMEGA—The International Journal of Management Science, 39 (3), 273-282.

Ruiz-Torres, A.J., F. Mahmoodi, and F. Lopez. (2010), ‘Supplier allocation and safety stock determination based on supplier reliability’. International Journal of Logistics Systems and Management, 7 (4), 412-430.

Ruiz-Torres, A.J., P. Santiago, and W. Chung. (2010), ‘The campaign and lot size scheduling problem: a modification of the economic lot scheduling problem for the pharmaceutical industry’. International Journal of Logistics Systems and Management, 7 (2), 184-197.

Ruiz-Torres, A. J., J. Zhang, J., E. Zapata, A. Pennathur, R. Rhodes, C. McCleskey, and M. Cowen. (2010), ‘A reliability, maintainability, and safety model to support the assessment of space vehicles’. International Journal of Quality and Reliability Management, 27 (4), 486-504.

Ruiz-Torres, A.J., F. Lopez, J. C. Ho, and P. J. Wojciechowski. (2010), ‘Parallel machine scheduling problems considering regular measures of performance and machine cost’. Journal of the Operational Research Society, 61, 849-857.

Ruiz-Torres, A.J. and F. Mahmoodi. (2010), 'Safety stock determination based on parametric lead time and demand information', International Journal of Production Research, 48 (10), 2841-2857.

Ruiz-Torres, A. J., J. Ablanedo-Rosas, and J. Ho. (2010), ' Minimizing the number of tardy jobs in the flowshop problem with operation and resource flexibility'. Computers and Operations Research, 37 (2), 282-291.

Ablanedo-Rosas, J. and A. J. Ruiz-Torres. (2009), 'Benchmarking of Mexican Ports with Data Envelopment Analysis’. International Journal of Shipping and Transport Logistics, 1 (3), 276-294.

Otero, L. D., G. Centeno, A. J. Ruiz-Torres, and C. E. Otero. (2009), ‘A systematic approach for resource allocation in software projects’. Computers & Industrial Engineering, 56 (4), 1333-1339.

Ho, J.C., B., Tseng, B., A. J. Ruiz-Torres, and F. Lopez. (2009), ‘Minimizing the normalized sum of square for workload deviations on m parallel processors’. Computers & Industrial Engineering, 56 (1), 186-192.

Ruiz-Torres, A.J. and F. Mahmoodi. (2008), ‘Analysis of multi-cell production systems considering cell size and worker flexibility’. International Journal of Industrial Engineering, 15 (4), 260-272.

Ho, J.C., A. J. Ruiz-Torres, F. Lopez, and T-L. Tseng. (2008), ‘Backward approach LPC-based constructive heuristic’. Journal of the Chinese Institute of Industrial Engineers, 25 (4), 275-286.

Ruiz-Torres, A.J., F. Lopez, J. C. Ho, and P. J. Wojciechowski. (2008), ‘Minimizing the average tardiness: the case of outsource machines’. International Journal of Production Research, 46 (13), 3615-3640.

Ruiz-Torres, A.J. and F. Mahmoodi. (2008), ‘Outsourcing decisions in manufacturing supply chains considering production failure and operating costs’. International Journal of Integrated Supply Management, 4 (2), 141-158.

Ruiz-Torres, A.J. and G. Centeno. (2008), ‘Minimizing the number of late jobs for the permutation flowshop problem with secondary resources’. Computers and Operations Research, 35 (4), 1227-1249.

Ruiz-Torres, A.J. and P. Santiago. (2007), ‘Inventory models considering post-production holding time and cost’. International Journal of Operations Research, 4 (4), 220-229.

Ruiz-Torres, A.J., F. Lopez, and J. C. Ho. (2007), ‘Scheduling uniform parallel machines subject to a secondary resource to minimize the number of tardy jobs’, European Journal of Operations Research, 179 (2), 302-315.

Ruiz-Torres, A. J. and F. Mahmoodi. (2007), ‘The optimal number of suppliers considering the costs of individual supplier failures’. OMEGA, 35, 104-115.

Ruiz-Torres, A.J. and G. Centeno. (2007), ‘Scheduling with flexible resources in parallel workcenters to minimize maximum completion time’. Computers and Operations Research, 34, 48-69.

Ruiz-Torres, A. J. and F. Mahmoodi. (2007), ‘Impact of worker and shop flexibility on assembly cells’. International Journal of Production Research, 45 (6), 1369-1388.

Ruiz-Torres, A. J., E. Zapata, K. Nakatani, and M. Cowen. (2006), ‘Knowledge based representation and operations assessment of space transportation system architectures’. Knowledge Based Systems, 19, 516-523.

Ruiz-Torres, A.J., J. C. Ho, and F. Lopez. (2006), ‘Generating Pareto schedules with outsource and internal parallel resources’. International Journal of Production Economics, 103, 810-825.

Ruiz-Torres, A.J. and F. Mahmoodi. (2006), ‘A supplier allocation model considering delivery failure, maintenance and supplier cycle costs’. International Journal of Production Economics, 103, 755-766.

Ruiz-Torres, A. J., E. Zapata, and M. Cowen. (2006), ‘Modeling of turnaround operations for next generation space transportation architectures’. International Journal of Industrial Engineering, 13(1), 18-27.

Gupta, J. N. D. and A. J. Ruiz-Torres. (2005), ‘Generating efficient schedules for identical parallel machines involving flow-time and tardy jobs’. European Journal of Operations Research, 167, 679-695.

Ruiz-Torres, A.J. and F. Lopez. (2004), ‘Using the FDH formulation of DEA to evaluate a multi-criteria problem in parallel machine scheduling’. Computers and Industrial Engineering Journal, 47 (2-3), 107-121.

Gupta, J.N.D., J. C. Ho, and A. J. Ruiz-Torres. (2004), ‘Makespan minimization on identical parallel machines subject to minimum mean flowtime’. Journal of the Chinese Institute of Industrial Engineers. 21 (3), 220-229.

Gupta, J. N.D., A. J. Ruiz-Torres, and S. Webster. (2003), ‘Minimizing maximum tardiness and number of tardy jobs on parallel machines subject to minimum flow-time’. Journal of the Operational Research Society, 54, 1263-1274.

Gonzalez-Torre, P. L., B. Adenso-Diaz, and A. J. Ruiz-Torres. (2003), 'Some comparative factors regarding recycling collections systems in regions of the USA and Europe’. Journal of Environmental Management, 69, 129-138.

Ali, S. I., K. Nakatani, and A.J. Ruiz-Torres, (2002), ‘The economics of a power minimization scheduling support system: a case study of petroleum products pipeline operations’. The Southern Business & Economic Journal, Spring 2002, 41-57.

Ruiz-Torres, A.J., (2002), ‘Group scheduling In parallel manufacturing cells with resource and family assignment flexibility’. International Journal of Industrial Engineering, 9 (2), 190-199.

Rodriguez, W., C. Fornaciari, J. Wynekoop, T. Harrington, K. Nakatani, A. J. Ruiz-Torres, D. Johnson, R. Boggs, and M. Pendergast, (2001), 'Information technology strategies for internet-based education'. Journal of Informatics in Education and Research, 3(1), Spring 2001, 26-40.

Gupta, J. and A. J. Ruiz-Torres, (2001), 'A LISTFIT heuristic for minimizing makespan on identical parallel machines'. Production Planning and Control Journal, 12(1), 28-36.

Gupta, J. and A. J. Ruiz-Torres, (2000), 'Minimizing makespan subject to minimum total flow-time on identical parallel machines'. European Journal of Operations Research, 125, 370-380.

Tyworth, J. E. and A. J. Ruiz-Torres, (2000), 'Transportation's role in the sole versus dual-sourcing decision'. International Journal of Physical Distribution and Logistics Management, 30, 128-144.

Ruiz-Torres, A. J., E. E. Enscore, and R. Barton, (1997), 'Simulated annealing heuristics for the average flow-time and the number of tardy jobs bi-criteria identical parallel machine problem'. Computers & Industrial Engineering, 33 (1/2), 257-260.