A scatter search algorithm for the distributed permutation flowshop scheduling problem

The distributed permutation flowshop problem has been recently proposed as a generalization of the regular flowshop setting where more than one factory is available to process jobs. Distributed manufacturing is a common situation for large enterprises that compete in a globalized market. The problem has two dimensions: assigning jobs to factories and scheduling the jobs assigned to each factory. Despite being recently introduced, this interesting scheduling problem has attracted attention and several heuristic and metaheuristic methods have been proposed in the literature. In this paper we present a scatter search (SS) method for this problem to optimize makespan. SS has seldom been explored for flowshop settings. In the proposed algorithm we employ some advanced techniques like a reference set made up of complete and partial solutions along with other features like restarts and local search. A comprehensive computational campaign including 10 existing algorithms, together with statistical analyses, shows that the proposed scatter search algorithm produces better results than existing algorithms by a significant margin. Moreover all 720 known best solutions for this problem are improved.Ruben Ruiz is partially supported by the Spanish Ministry of Economy and Competitiveness, under the project "RESULT - Realistic Extended Scheduling Using Light Techniques" with reference DPI2012-36243-C02-01 co-financed by the European Union and FEDER funds and by the Universitat Politecnica de Valencia, for the project MRPIV with reference PAID/2012/202.Naderi, B.; Ruiz García, R. (2014). A scatter search algorithm for the distributed permutation flowshop scheduling problem. European Journal of Operational Research. 239(2):323-334. https://doi.org/10.1016/j.ejor.2014.05.024S323334239

Protocolo de Cooperación Adaptativo para Sistemas de Comunicaciones Opticas Atmosféricas

En concreto, se ha analizado un sistema de comunicaciones cooperativas formado por 3 enlaces FSO con retransmision DF usando IM/DD sobre canales con turbulencia atmosferica y desalineamiento entre el transmisor y el receptor. Se han evaluado las prestaciones de un protocolo de cooperacion adaptativo basado en la seleccion de camino óptico con mayor valor de irradiancia.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Size-reduction heuristics for the unrelated parallel machines scheduling problem

[EN] In this paper we study the unrelated parallel machines problem where n independent jobs must be assigned to one out of m parallel machines and the processing time of each job differs from machine to machine. We deal with the objective of the minimisation of the maximum completion time of the jobs, usually referred to as makespan or Cmax. This is a type of assignment problem that has been frequently studied in the scienti¿c literature due to its many potential applications. We propose a set of metaheuristics based on a size-reduction of the original assignment problem that produce solutions of very good quality in a short amount of time. The underlying idea is to consider only a few of the best possible machine assignments for the jobs and not all of them. The results are simple, yet powerful methods. We test the proposed algorithms with a large benchmark of instances and compare them with current state-of-the-art methods. In most cases, the proposed size-reduction algorithms produce results that are statistically proven to be better by a signi¿cant margin. & 2010 Elsevier Ltd. All rights reservedThis work is partially funded by the Spanish Ministry of Science and Innovation, under the project ‘‘SMPA—Advanced Parallel Multiobjective Sequencing: Practical and Theoretical Advances’’ with references number DPI2008-03511/DPI. The authors should also thank the IMPIVA—Institute for the Small and Medium Valencian Enterprise, for the project OSC with reference IMIDIC/2008/137 and the Polytechnic University of Valencia, for the project PPAR with reference 3147.Fanjul Peyró, L.; Ruiz García, R. (2011). Size-reduction heuristics for the unrelated parallel machines scheduling problem. Computers and Operations Research. 38(1):301-309. https://doi.org/10.1016/j.cor.2010.05.005S30130938

A comprehensive review and evaluation of permutation flowshop heuristics to minimize flowtime

[EN] In recent years, a large number of heuristics have been proposed for the minimization of the total or mean flowtime/completion time of the well-known permutation flowshop scheduling problem. Although some literature reviews and comparisons have been made, they do not include the latest available heuristics and results are hard to compare as no common benchmarks and computing platforms have been employed. Furthermore, existing partial comparisons lack the application of powerful statistical tools. The result is that it is not clear which heuristics, especially among the recent ones, are the best. This paper presents a comprehensive review and computational evaluation as well as a statistical assessment of 22 existing heuristics. From the knowledge obtained after such a detailed comparison, five new heuristics are presented. Careful designs of experiments and analyses of variance (ANOVA) techniques are applied to guarantee sound conclusions. The comparison results identify the best existing methods and show that the five newly presented heuristics are competitive or better than the best performing ones in the literature for the permutation flowshop problem with the total completion time criterionThis research is partially supported by National Science Foundation of China (60874075, 61174187), and Science Foundation of Shandong Province, China (BS2010DX005), and Postdoctoral Science Foundation of China (20100480897). Ruben Ruiz is partially funded by the Spanish Ministry of Science and Innovation, under the project "SMPA-Advanced Parallel Multiobjective Sequencing: Practical and Theorerical Advances" with reference DPI2008-03511/DPI and by the Small and Medium Industry of the Generalitat Valenciana (IMPIVA) and by the European Union through the European Regional Development Fund (FEDER) inside the R+D program "Ayudas dirigidas a Institutos Tecnologicos de la Red IMPIVA" during the year 2011, with project number IMDEEA/2011/142.Pan, Q.; Ruiz García, R. (2013). A comprehensive review and evaluation of permutation flowshop heuristics to minimize flowtime. Computers and Operations Research. 40(1):117-128. https://doi.org/10.1016/j.cor.2012.05.018S11712840

Scheduling unrelated parallel machines with resource-assignable sequence-dependent setup times

[EN] A novel scheduling problem that results from the addition of resource-assignable setups is presented in this paper. We consider an unrelated parallel machine problem with machine and job sequence-dependent setup times. The new characteristic is that the amount of setup time does not only depend on the machine and job sequence but also on the amount of resources assigned, which can vary between a minimum and a maximum. The aim is to give solution to real problems arising in several industries where frequent setup operations in production lines have to be carried out. These operations are indeed setups whose length can be reduced or extended according to the amount of resources assigned to them. The objective function considered is a linear combination of total completion time and the total amount of resources assigned. We present a mixed integer program (MIP) model and some fast dispatching heuristics. We carry out careful and comprehensive statistical analyses to study what characteristics of the problem affect the MIP model performance. We also study the effectiveness of the different heuristics proposed. © 2011 Springer-Verlag London Limited.The authors are indebted to the referees and editor for a close examination of the paper, which has increased its quality and presentation. This work is partially funded by the Spanish Ministry of Science and Innovation, under the project "SMPA-Advanced Parallel Multiobjective Sequencing: Practical and Theoretical Advances" with reference DPI2008-03511/DPI. The authors should also thank the IMPIVA-Institute for the Small and Medium Valencian Enterprise, for the project OSC with references IMIDIC/2008/137, IMIDIC/2009/198, and IMIDIC/2010/175.Ruiz García, R.; Andrés Romano, C. (2011). Scheduling unrelated parallel machines with resource-assignable sequence-dependent setup times. International Journal of Advanced Manufacturing Technology. 57(5):777-794. https://doi.org/10.1007/S00170-011-3318-2S777794575Allahverdi A, Gupta JND, Aldowaisan T (1999) A review of scheduling research involving setup considerations. OMEGA Int J Manag Sci 27(2):219–239Allahverdi A, Ng CT, Cheng TCE, Kovalyov MY (2008) A survey of scheduling problems with setup times or costs. Eur J Oper Res 187(3):985–1032Balakrishnan N, Kanet JJ, Sridharan SV (1999) Early/tardy scheduling with sequence dependent setups on uniform parallel machines. Comput Oper Res 26(2):127–141Biggs D, De Ville B, and Suen E (1991) A method of choosing multiway partitions for classification and decision trees. J Appl Stat 18(1):49–62Chen J-F (2006) Unrelated parallel machine scheduling with secondary resource constraints. Int J Adv Manuf Technol 26(3):285–292Cheng TCE, Sin CCS (1990) A state-of-the-art review of parallel machine scheduling research. Eur J Oper Res 47(3):271–292Graham RL, Lawler EL, Lenstra JK, Rinnooy Kan AHG (1979) Optimization and approximation in deterministic sequencing and scheduling: a survey. Ann Discrete Math 5:287–326Grigoriev E, Sviridenko M, Uetz M (2007) Unrelated parallel machine scheduling with resource dependent processing times. Math Program Ser A and B 110(1):209–228Guinet A (1991) Textile production systems: a succession of non-identical parallel processor shops. J Oper Res Soc 42(8):655–671Guinet A, Dussauchoy A (1993) Scheduling sequence dependent jobs on identical parallel machines to minimize completion time criteria. Int J Prod Res 31(7):1579–1594Horn WA (1973) Minimizing average flow time with parallel machines. Oper Res 21(3):846–847Kass GV (1980) An exploratory technique for investigating large quantities of categorical data. Appl Stat 29(2):119–127Kim DW, Kim KH, Jang W, Chen FF (2002) Unrelated parallel machine scheduling with setup times using simulated annealing. Robot Comput-Integr Manuf 18(3–4):223–231Lam K, Xing W (1997) New trends in parallel machine scheduling. Int J Oper Prod Manage 17(3):326–338Lee YH, Pinedo M (1997) Scheduling jobs on parallel machines with sequence dependent setup times. Eur J Oper Res 100(3):464–474Marsh JD, Montgomery DC (1973) Optimal procedures for scheduling jobs with sequence-dependent changeover times on parallel processors. AIIE Technical Papers, pp 279–286Mokotoff E (2001) Parallel machine scheduling problems: a survey. Asia-Pac J Oper Res 18(2):193–242Morgan JA, Sonquist JN (1963) Problems in the analysis of survey data and a proposal. J Am Stat Assoc 58:415–434Ng CT, Edwin Cheng TC, Janiak A, Kovalyov MY (2005) Group scheduling with controllable setup and processing times: minimizing total weighted completion time. Ann Oper Res 133:163–174Nowicki E, Zdrzalka S (1990) A survey of results for sequencing problems with controllable processing times. Discrete Appl Math 26(2–3):271–287Pinedo M (2002) Scheduling: theory, algorithms, and systems, 2nd edn. Prentice Hall, Upper SaddleRabadi G, Moraga RJ, Al-Salem A (2006) Heuristics for the unrelated parallel machine scheduling problem with setup times. J Intell Manuf 17(1):85–97Radhakrishnan S, Ventura JA (2000) Simulated annealing for parallel machine scheduling with earliness-tardiness penalties and sequence-dependent set-up times. Int J Prod Res 38(10):2233–2252Ruiz R, Sivrikaya Şerifoğlu F, Urlings T (2008) Modeling realistic hybrid flexible flowshop scheduling problems. Comput Oper Res 35(4):1151–1175Sivrikaya-Serifoglu F, Ulusoy G (1999) Parallel machine scheduling with earliness and tardiness penalties. Comput Oper Res 26(8):773–787Webster ST (1997) The complexity of scheduling job families about a common due date. Oper Res Lett 20(2):65–74Weng MX, Lu J, Ren H (2001) Unrelated parallel machines scheduling with setup consideration and a total weighted completion time objective. Int J Prod Econ 70(3):215–226Yang W-H, Liao C-J (1999) Survey of scheduling research involving setup times. Int J Syst Sci 30(2):143–155Zhang F, Tang GC, Chen ZL (2001) A 3/2-approximation algorithm for parallel machine scheduling with controllable processing times. Oper Res Lett 29(1):41–47Zhu Z, Heady R (2000) Minimizing the sum of earliness/tardiness in multi-machine scheduling: a mixed integer programming approach. Comput Ind Eng 38(2):297–30

A study on the effect of the asymmetry on real capacitated vehicle routing problems

Matrices with distances between pairs of locations are essential for solving vehicle routing problems like the Capacitated Vehicle Routing Problem (CVRP), Traveling Salesman Problem (TSP) and others. This work deals with the complex reality of transportation networks and asymmetry. Through a series of comprehensive and thorough computational and statistical experiments we study the effect that many factors like asymmetry, geographical location of the depot and clients, demand, territory and maximum vehicle capacity have in the solution of CVRP instances. We examine both classical heuristics as well as current state-of-the-art metaheuristics and show that these methods are seriously affected by the studied factors from a solution time and quality of solutions perspective. We systematically compare the solutions obtained in the symmetric scenario with those obtained in the real asymmetric case at a quantitative as well as a qualitative level, with the objective of carefully measuring and understanding the differences between both cases. © 2011 Elsevier Ltd.The authors are indebted to Keld Helsgaun, Stefan Ropke and especially to Yuichi Nagata for their kind help, collaboration and for facilitating the binaries of their algorithms. This work is partially funded by the Spanish Ministry of Science and Innovation, under the project "SMPA-Advanced Parallel Multiobjective Sequencing: Practical and Theoretical Advances" with reference DPI2008-03511/DPI. The authors should also thank the IMPIVA-Institute for the Small and Medium Valencian Enterprise, for the project TASER with reference IMDEEA/2011/142.Rodríguez Villalobos, A.; Ruiz García, R. (2012). A study on the effect of the asymmetry on real capacitated vehicle routing problems. Computers and Operations Research. 39(9):2142-2151. https://doi.org/10.1016/j.cor.2011.10.023S2142215139

Evaluating pointing errors on ergodic capacity of DF relay-assisted FSO communication systems

Ergodic capacity of decode-and-forward (DF) relay-assisted free-space optical (FSO) communication systems when line of sight is available is analyzed over gamma-gamma fading channels with pointing errors. Novel closed-form approximate ergodic capacity expression is obtained in terms of the H-Fox function for a 3-way FSO communication system when the α-μ distribution to efficiently approximate the probability density function (PDF) of the sum of gamma-gamma with pointing errors variates is considered. Moreover, we present a novel asymptotic expression at high signal-to-noise ratio (SNR) for the ergodic capacity of DF relay-assisted FSO systems. The main contribution in this work lies in an in-depth analysis about the impact of pointing errors on the ergodic capacity for cooperative FSO systems. In order to maintain the same performance in terms of capacity, it is corroborated that the presence of pointing errors requires an increase in SNR, which is related to the fraction of the collected power at the receive aperture, i.e. A 0 . Simulation results are further demonstrated to confirm the accuracy and usefulness of the derived results.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. The authors wish to acknowledge the financial support given by Spanish MINECO Project TEC2012-32606

Heuristics for periodical batch job scheduling in a MapReduce computing framework

Task scheduling has a significant impact on the performance of the MapReduce computing framework. In this paper, a scheduling problem of periodical batch jobs with makespan minimization is considered. The problem is modeled as a general two-stage hybrid flow shop scheduling problem with schedule-dependent setup times. The new model incorporates the data locality of tasks and is formulated as an integer program. Three heuristics are developed to solve the problem and an improvement policy based on data locality is presented to enhance the methods. A lower bound of the makespan is derived. 150 instances are randomly generated from data distributions drawn from a real cluster. The parameters involved in the methods are set according to different cluster setups. The proposed heuristics are compared over different numbers of jobs and cluster setups. Computational results show that the performance of the methods is highly dependent on both the number of jobs and the cluster setups. The proposed improvement policy is effective and the impact of the input data distribution on the policy is analyzed and tested.This work is supported by the National Natural Science Foundation of China (No. 61272377) and the Specialized Research Fund for the Doctoral Program of Higher Education (No. 20120092110027). Ruben Ruiz is partially supported by the Spanish Ministry of Economy and Competitiveness, under the project "RESULT - Realistic Extended Scheduling Using Light Techniques" (No. DPI2012-36243-C02-01) partially financed with FEDER funds.Xiaoping Li; Tianze Jiang; Ruiz García, R. (2016). Heuristics for periodical batch job scheduling in a MapReduce computing framework. Information Sciences. 326:119-133. https://doi.org/10.1016/j.ins.2015.07.040S11913332

Benders decomposition for the mixed no-idle permutation flowshop scheduling problem

[EN] The mixed no-idle flowshop scheduling problem arises in modern industries including integrated circuits, ceramic frit and steel production, among others, and where some machines are not allowed to remain idle between jobs. This paper describes an exact algorithm that uses Benders decomposition with a simple yet effective enhancement mechanism that entails the generation of additional cuts by using a referenced local search to help speed up convergence. Using only a single additional optimality cut at each iteration, and combined with combinatorial cuts, the algorithm can optimally solve instances with up to 500 jobs and 15 machines that are otherwise not within the reach of off-the-shelf optimization software, and can easily surpass ad-hoc existing metaheuristics. To the best of the authors' knowledge, the algorithm described here is the only exact method for solving the mixed no-idle permutation flowshop scheduling problem.This research project was partially supported by the Scientific and Technological Research Council of Turkey (TuBITAK) under Grant 1059B191600107. While writing this paper, Dr Hamzaday was a visiting researcher at the Southampton Business School at the University of Southampton. Ruben Ruiz is supported by the Spanish Ministry of Science, Innovation and Universities, under the Project 'OPTEP-Port Terminal Operations Optimization' (No. RTI2018-094940-B-I00) financed with FEDER funds. Thanks are due to two anonymous reviewers for their careful reading of the paper and helpful suggestions.Bektas, T.; Hamzadayi, A.; Ruiz García, R. (2020). Benders decomposition for the mixed no-idle permutation flowshop scheduling problem. Journal of Scheduling. 23(4):513-523. https://doi.org/10.1007/s10951-020-00637-8S513523234Adiri, I., & Pohoryles, D. (1982). Flowshop no-idle or no-wait scheduling to minimize the sum of completion times. Naval Research Logistics, 29(3), 495–504.Baker, K. R. (1974). Introduction to sequencing and scheduling. New York: Wiley.Baptiste, P., & Hguny, L. K. (1997). A branch and bound algorithm for the $$F$$/no-idle/$$C_{max}$$. In Proceedings of the international conference on industrial engineering and production management, IEPM’97, Lyon, France (Vol. 1, pp. 429–438).Benders, J. F. (1962). Partitioning procedures for solving mixed-variables programming problems. Numerische Mathematik, 4(1), 238–252.Cordeau, J. F., Pasin, F., & Solomon, M. (2006). An integrated model for logistics network design. Annals of Operations Research, 144(1), 59–82.Costa, A. M., Cordeau, J. F., Gendron, B., & Laporte, G. (2012). Accelerating benders decomposition with heuristic master problem solutions. Pesquisa Operacional, 32(1), 3–20.Deng, G., & Gu, X. (2012). A hybrid discrete differential evolution algorithm for the no-idle permutation flow shop scheduling problem with makespan criterion. Computers & Operations Research, 39(9), 2152–2160.Goncharov, Y., & Sevastyanov, S. (2009). The flow shop problem with no-idle constraints: A review and approximation. European Journal of Operational Research, 196(2), 450–456.Kalczynski, P. J., & Kamburowski, J. (2005). A heuristic for minimizing the makespan in no-idle permutation flow shops. Computers & Industrial Engineering, 49(1), 146–154.Magnanti, T. L., & Wong, R. T. (1981). Accelerating benders decomposition: Algorithmic enhancement and model selection criteria. Operations Research, 29(3), 464–484.Pan, Q. K., & Ruiz, R. (2014). An effective iterated greedy algorithm for the mixed no-idle flowshop scheduling problem. Omega, 44(1), 41–50.Pan, Q. K., Tasgetiren, M. F., & Liang, Y. C. (2008). A discrete differential evolution algorithm for the permutation flowshop scheduling problem. Computers & Industrial Engineering, 55(4), 795–816.Pan, Q. K., & Wang, L. (2008a). No-idle permutation flow shop scheduling based on a hybrid discrete particle swarm optimization algorithm. International Journal of Advanced Manufacturing Technology, 39(7–8), 796–807.Pan, Q. K., & Wang, L. (2008b). A novel differential evolution algorithm for no-idle permutation flow-shop scheduling problems. European Journal of Industrial Engineering, 2(3), 279–297.Papadakos, N. (2008). Practical enhancements to the Magnanti–Wong method. Operations Research Letters, 36(4), 444–449.Röck, H. (1984). The three-machine no-wait flow shop is NP-complete. Journal of the Association for Computing Machinery, 31(2), 336–345.Ruiz, R., & Maroto, C. (2005). A comprehensive review and evaluation of permutation flowshop heuristics. European Journal of Operational Research, 165(2), 479–494.Ruiz, R., Vallada, E., & Fernández-Martínez, C. (2009). Scheduling in flowshops with no-idle machines. In U. Chakraborty (Ed.), Computational intelligence in flow shop and job shop scheduling, chap 2 (pp. 21–51). New York: Springer.Saadani, N. E. H., Guinet, A., & Moalla, M. (2003). Three stage no-idle flow-shops. Computers & Industrial Engineering, 44(3), 425–434.Saharidis, G., & Ierapetritou, M. (2013). Speed-up Benders decomposition using maximum density cut (MDC) generation. Annals of Operations Research, 210, 101–123.Shao, W., Pi, D., & Shao, Z. (2017). Memetic algorithm with node and edge histogram for no-idle flow shop scheduling problem to minimize the makespan criterion. Applied Soft Computing, 54, 164–182.Tasgetiren, M. F., Buyukdagli, O., Pan, Q. K., & Suganthan, P. N. (2013). A general variable neighborhood search algorithm for the no-idle permutation flowshop scheduling problem. In B. K. Panigrahi, P. N. Suganthan, S. Das, & S. S. Dash (Eds.), Swarm, evolutionary, and memetic computing (pp. 24–34). Cham: Springer.Vachajitpan, P. (1982). Job sequencing with continuous machine operation. Computers & Industrial Engineering, 6(3), 255–259

Resource Provisioning for Task-Batch Based Workflows with Deadlines in Public Clouds

[EN] To meet the dynamic workload requirements in widespread task-batch based workflow applications, it is important to design algorithms for DAG-based platforms (such as Dryad, Spark and Pegasus) to rent virtual machines from public clouds dynamically. In terms of depths and functionalities, tasks of different task-batches are merged into task-units. A unit-aware deadline division method is investigated for properly dividing workflow deadlines to task deadlines so as to minimize the utilization of rented intervals. A rule-based task scheduling method is presented for allocating tasks to time slots of rented Virtual Machines (VMs) with a task right shifting operation and a weighted priority composite rule. A Unit-aware Rule-based Heuristic (URH) is proposed for elastically provisioning VMs to task-batch based workflows to minimize the rental cost in DAG-based cloud platforms. Effectiveness of the proposed URH methods is verified by comparing them against two adapted existing algorithms for similar problems on some realistic workflows.The authors would like to thank the reviewers for their constructive and useful comments. This work is supported by the National Natural Science Foundation of China (Grant No.61602243 and 61572127), the Natural Science Foundation of Jiangsu Province (Grant No.BK20160846), the Jiangsu Key Laboratory of Image and Video Understanding for Social Safety (Grant No. 30916014107). Ruben Ruiz is partially supported by the Spanish Ministry of Economy and Competitiveness, under the project "SCHEYARD" (DPI2015-65895-R) financed by FEDER funds.Cai, Z.; Li, X.; Ruiz García, R. (2019). Resource Provisioning for Task-Batch Based Workflows with Deadlines in Public Clouds. IEEE Transactions on Cloud Computing. 7(3):814-826. https://doi.org/10.1109/TCC.2017.2663426S8148267