@article{balkumar_gedam_himateja_anbuudayasankar_s_ganesh_dwarakanath_pazhani_2023, title={Prevalence and future trend in green supply chain management (GSCM): a systematic literature review}, url={http://dx.doi.org/10.1108/bij-06-2022-0363}, DOI={10.1108/bij-06-2022-0363}, abstractNote={PurposeOver the last two decades, green supply chain management (GSCM) has enabled businesses to operate in an environmentally friendly manner. The present review examines 234 research articles and proposes a methodical literature review on GSCM, focusing on the aspects of sustainable development.}, journal={Benchmarking: An International Journal}, author={Balkumar, Kartik and GEDAM, VIDYADHAR and Himateja, Mudunuri and ANBUUDAYASANKAR, S.P. and S, Narassima M and Ganesh, K. and Dwarakanath, M. and Pazhani, Subramanian}, year={2023}, month={Jun} }
 @article{kungwalsong_mendoza_kamath_pazhani_marmolejo-saucedo_2022, title={An application of interactive fuzzy optimization model for redesigning supply chain for resilience}, volume={315}, ISSN={0254-5330 1572-9338}, url={http://dx.doi.org/10.1007/s10479-022-04542-5}, DOI={10.1007/s10479-022-04542-5}, abstractNote={Abstract}, number={2}, journal={Annals of Operations Research}, publisher={Springer Science and Business Media LLC}, author={Kungwalsong, Kanokporn and Mendoza, Abraham and Kamath, Vasanth and Pazhani, Subramanian and Marmolejo-Saucedo, Jose Antonio}, year={2022}, month={Feb}, pages={1803–1839} }
 @article{adeinat_pazhani_mendoza_ventura_2022, title={Coordination of pricing and inventory replenishment decisions in a supply chain with multiple geographically dispersed retailers}, volume={248}, ISSN={0925-5273}, url={http://dx.doi.org/10.1016/j.ijpe.2022.108461}, DOI={10.1016/j.ijpe.2022.108461}, abstractNote={We study the efficiency of a multi-stage supply chain controlled by a single decision-maker with the goal of maximizing the total profit per time unit for a single product by coordinating the purchasing of raw materials from an external supplier, manufacturing and shipping the product between consecutive stages, and determining the selling price and final demand for the product sold by multiple retailers. Retailers are geographically dispersed, control their own market areas, and differ in terms of operating costs and marketing strategies. Each retailer has a different price-sensitive demand function. In this study, we propose a mixed integer nonlinear programming model that maximizes the total profit per time unit, which includes the revenue of the final product, echelon holding costs, and fixed costs for ordering and shipping items at each stage and at each retailer location. Using a numerical example, we show that the model with varying selling prices at the retailers yields higher profits than the model with the same selling price across all the retailers. We also perform an analysis comparing the coordinated approach versus the sequential approach for pricing and inventory replenishment decisions by varying the market size and demand function parameters. The results show that, as the market size parameter decreases, the coordinated approach yields a higher profit than the sequential approach does. Additionally, given a constant market size setting, the results show that pricing and inventory replenishment decisions are very sensitive to the demand function parameters. The analysis also shows that the coordinated approach yields an average profit gain of 24.18% compared to the profit of 3.53% yielded by the sequential approach. Similarly, it is shown that the coordinated approach always yields a better profit than the sequential approach across all scenarios generated by varying the demand parameters. Moreover, we propose a Simulated Annealing (SA) algorithm to obtain near-optimal solutions in a timely manner. A computational comparison shows that the average solution reached by the proposed SA algorithm is at 0.04% from the optimal solution.}, journal={International Journal of Production Economics}, publisher={Elsevier BV}, author={Adeinat, Hamza and Pazhani, Subramanian and Mendoza, Abraham and Ventura, Jose A.}, year={2022}, month={Jun}, pages={108461} }
 @book{pazhani_2021, title={Design and Analysis of Closed-Loop Supply Chain Networks}, url={https://books.google.com/books?id=FNQhEAAAQBAJ}, publisher={CRC Press}, author={Pazhani, S.}, year={2021} }
 @article{pazhani_mendoza_nambirajan_narendran_ganesh_olivares-benitez_2021, title={Multi-period multi-product closed loop supply chain network design: A relaxation approach}, volume={155}, ISSN={0360-8352}, url={http://dx.doi.org/10.1016/j.cie.2021.107191}, DOI={10.1016/j.cie.2021.107191}, abstractNote={Growing concern about environmental deterioration, manifested in new laws to protect the environment and business competition, has stimulated the idea of Closed Loop Supply Chains (CLSC). This paper develops strategic decision-making models for two different CLSCs with multiple products over multiple periods. One of the networks has six levels, while the other has four levels, and they can be applied to products with different levels of complexity during inspection and remanufacturing operations. The supply chain networks are modeled as Integer Linear Programs (ILP) designed to assist decision-making in terms of location/allocation, transportation, and inventory. Taking advantage of the properties of the formulations, we propose an integer relaxation approach to obtain the optimal solution to ILP. The proposed models and methodologies are illustrated with case studies from the literature and with hypothetical datasets. This research contributes with design standard configurations for CLSCs that can be used for different types of products. Directly using these configurations is advantageous because the models proposed can be quickly solved using the integer relaxation approach. The associated trials confirm the utility of the models for the case studies and demonstrate encouraging results for the hypothetical datasets.}, journal={Computers & Industrial Engineering}, publisher={Elsevier BV}, author={Pazhani, Subramanian and Mendoza, Abraham and Nambirajan, Ramkumar and Narendran, T.T. and Ganesh, K. and Olivares-Benitez, Elias}, year={2021}, month={May}, pages={107191} }
 @article{nambirajan_mendoza_pazhani_narendran_ganesh_2020, title={CAR: heuristics for the inventory routing problem}, volume={26}, ISSN={1022-0038 1572-8196}, url={http://dx.doi.org/10.1007/s11276-020-02259-6}, DOI={10.1007/s11276-020-02259-6}, number={8}, journal={Wireless Networks}, publisher={Springer Science and Business Media LLC}, author={Nambirajan, Ramkumar and Mendoza, Abraham and Pazhani, Subramanian and Narendran, T. T. and Ganesh, K.}, year={2020}, month={Jan}, pages={5783–5808} }
 @inproceedings{pazhani_beeg_zmithrovitch_lazo_2019, title={Volume-based Prioritization for Lot Dispatching and Mathematical Model Based Lot Scheduling for Nikon Tools}, booktitle={Cree | Wolfspeed Innovation Summit}, author={Pazhani, Subramanian and Beeg, Thomas and Zmithrovitch, Katrina and Lazo, Nathan}, year={2019} }
 @article{pazhani_beeg_kowalczyk_dietrich_2018, title={A bi-criteria mixed integer linear programming model for load balancing and chemical saving in wafer cleaning processes: IE: Industrial engineering}, url={http://dx.doi.org/10.1109/asmc.2018.8373188}, DOI={10.1109/asmc.2018.8373188}, abstractNote={Semiconductor manufacturing or wafer fabrication process involves multiple processing steps and is highly re-entrant, where a job may visit an equipment group more than once, at various stages of the product flow. Wafer cleaning process in semiconductor fabrication comprises multiple steps at various stages of the product flow to remove particles and oxidize organic contaminants, using different chemicals. This paper focusses on front-end of the line wafer cleaning steps. We consider J equipment groups which run I clean process steps and uses M different chemicals. Each step is qualified to run on a set of equipment groups and when recipes using different chemical run back to back on a tool-there is a chemical pre-dispense to clean and condition the nozzle. Given today's increasingly cost-conscious and competitive market, this study focuses on balancing loads on the equipment groups and minimize operating cost by reducing chemical pre-dispenses. We propose a bi-criteria mixed integer linear programming model to allocate daily demands to the equipment groups with the objectives of minimizing the maximum utilization and reducing chemical pre-dispenses. We also propose a priority based dispatching algorithm to translate the model output and implement in a dispatching system. Results show that the model reduces chemical pre-dispense resulting in significant cost saving, improved throughput due to cascading, and balanced utilization across the equipment groups.}, journal={2018 29th Annual SEMI Advanced Semiconductor Manufacturing Conference (ASMC)}, author={Pazhani, Subramanian and Beeg, Thomas and Kowalczyk, Kristopher and Dietrich, Todd}, year={2018}, month={Apr} }
 @article{pazhani_ravindran_2018, title={A bi-criteria model for closed loop supply chain network design}, volume={31}, ISSN={1745-7645 1745-7653}, url={http://dx.doi.org/10.1504/ijor.2018.089735}, DOI={10.1504/ijor.2018.089735}, abstractNote={Closed loop supply chains (CLSC) are the integration of both forward and reverse supply chains. The integration is important as independent operations and management of forward and reverse supply chains lead to a reduction in efficiency in the supply chain as a whole. This article considers a four-stage CLSC network with commercial returns, which could be potentially recovered by light repair operations or by refurbishing. The annual estimate of commercial returns in the USA is in excess of $100 billion. This paper discusses the optimal design of a CLSC network with the objectives of maximising the profit of the supply chain and minimising the energy usage at the warehousing facilities and energy consumed during transportation. A bi-criteria mixed integer linear programming (MILP) model is developed to determine the optimal locations of the facilities and the distribution of flows between facilities in the CLSC. We propose an interactive optimisation algorithm to systematically solve the bi-criteria problem which poses less cognitive burden on the decision maker and converges faster to the best compromise solution.}, number={3}, journal={International Journal of Operational Research}, publisher={Inderscience Publishers}, author={Pazhani, Subramanian and Ravindran, A. Ravi}, year={2018}, pages={330} }
 @article{method and system to automatically generate throughput for semiconductor tools_2018, year={2018}, month={Jan} }
 @inbook{pazhani_2017, title={A Bi-Criteria Model for Closed-Loop Supply Chain Network Design Incorporating Customer Behavior}, booktitle={Multiple Criteria Decision Making in Supply Chain Management}, publisher={CRC Press}, author={Pazhani, Subramanian}, year={2017}, pages={243–284} }
 @inproceedings{pazhani_beeg_2017, title={Analyzing different strategies of continuous improvement programs on repair times to reduce cycle time}, booktitle={GLOBALFOUNDRIES & IEEE EDS Technology Forum}, author={Pazhani, Subramanian and Beeg, Thomas}, year={2017}, month={Sep} }
 @inproceedings{arjunwadkar_pazhani_patel_2017, title={Enhancing Capacity Planning model using Simulation}, booktitle={GLOBALFOUNDRIES & IEEE EDS Technology Forum}, author={Arjunwadkar, Vikram and Pazhani, Subramanian and Patel, Rahul}, year={2017}, month={Sep} }
 @inproceedings{wribhu_pazhani_2017, title={Optimization based grouping algorithm to create dispatch station families}, booktitle={GLOBALFOUNDRIES & IEEE EDS Technology Forum}, author={Wribhu, Atirek and Pazhani, Subramanian}, year={2017}, month={Sep} }
 @article{pazhani_ventura_mendoza_2016, title={A serial inventory system with supplier selection and order quantity allocation considering transportation costs}, volume={40}, ISSN={0307-904X}, url={http://dx.doi.org/10.1016/j.apm.2015.06.008}, DOI={10.1016/j.apm.2015.06.008}, abstractNote={Given the importance of incorporating transportation costs in inventory replenishment and supplier selection decisions, this article addresses the issue of supplier selection and order quantity allocation in a multi-stage serial supply chain system with multiple suppliers considering inventory replenishment, holding, and transportation costs simultaneously. We propose a mixed integer nonlinear programming model to determine the optimal inventory policy for the stages in the supply chain and allocation of orders among the suppliers at the initial stage. Transportation costs between consecutive stages are modeled using a piecewise constant setup cost structure arising from a full truckload freight rate cost model. Vehicles of different capacities are available to transport materials from the suppliers to the manufacturing facility and between the remaining stages of the supply chain. The usefulness of the model is discussed with an example. Sensitivity analysis is carried out to determine the effect of cost parameters on supplier order allocation. The analysis shows that the selection of suppliers and the corresponding order quantities are affected by the variations in supply chain costs parameters. In addition, the advantages of using an integrated approach versus a sequential approach for inventory replenishment and supplier selection decisions are shown. Computational results show that the integrated approach yields average savings of 4.88% in total cost and 15.31% in logistics costs over the sequential approach.}, number={1}, journal={Applied Mathematical Modelling}, publisher={Elsevier BV}, author={Pazhani, Subramanian and Ventura, José A. and Mendoza, Abraham}, year={2016}, month={Jan}, pages={612–634} }
 @article{nambirajan_mendoza_pazhani_narendran_ganesh_2016, title={CARE: Heuristics for two-stage multi-product inventory routing problems with replenishments}, volume={97}, ISSN={0360-8352}, url={http://dx.doi.org/10.1016/j.cie.2016.04.004}, DOI={10.1016/j.cie.2016.04.004}, abstractNote={The integration of distribution and routing constitutes the Inventory Routing Problem (IRP), an important aspect of Vendor Managed Inventory (VMI) systems. IRP involves decisions on timing of deliveries, sizes of shipments and routing of vehicles. In the context of supply chain collaboration, the scope of IRP expands to include replenishments at the depot. This paper studies an IRP involving multiple products from different suppliers, a central depot (CD) and a set of warehouses. We develop an integrated Integer Linear Programming (ILP) model to determine the optimal replenishments from suppliers to the CD as well as the routing schedules of vehicles from CD to the multiple warehouses over the defined time horizon. We propose an extended three-phase heuristic called CARE (Clustering, Allocation, Routing -Extended). In the heuristic, the replenishment schedules, from suppliers to the CD (for multiple products in the defined time horizon), is solved using a dynamic programming (DP) model. The routing schedules of vehicles from CD to the multiple warehouses is then modeled and solved as a capacitated IRP (CIRP) problem. With the replenishment schedules as an input from the DP model, the CIRP is solved in three-phases: Cluster the nodes, Allocate to these nodes and Route delivery vehicles through clusters of nodes. Three variants of heuristics are proposed based on the changes to the routing phase – CARE1, CARE2, and CARE3. Computational results for a broad range of test instances yield promising results and show usefulness of the solution approaches. Particularly, the proposed heuristics outperformed CPLEX upper bounds for larger problems with lesser computational effort. The average improvement obtained by the heuristics over CPLEX upper bounds for 15 and 20 warehouse problems, respectively, are: CARE1 – 0.94% and 3.6%, CARE2 – 1.36% and 4.26%, CARE3 – 2.87% and 6.08%. We also show that the results from the proposed heuristic are statistically better than the CPLEX upper bounds. The proposed approaches can easily be implemented into existing VMI systems.}, journal={Computers & Industrial Engineering}, publisher={Elsevier BV}, author={Nambirajan, Ramkumar and Mendoza, Abraham and Pazhani, Subramanian and Narendran, T.T. and Ganesh, K.}, year={2016}, month={Jul}, pages={41–57} }
 @article{pazhani_chakravarthi_adhikari_2016, title={Rapid unconstrained fab model using a business intelligence tool: DM: Data management and data mining tools}, url={http://dx.doi.org/10.1109/asmc.2016.7491130}, DOI={10.1109/asmc.2016.7491130}, abstractNote={Semiconductor FABs operate with dynamic demand and supply changes as compared to any other industry. The industry traditionally uses spreadsheet based capacity models as well as more sophisticated tools such as Advanced Planning & Scheduling and/or Discrete Event Simulation software. While spreadsheet models are great for simple scenarios, fab managers are increasingly relying more on non-spreadsheet engines. Non-spreadsheet methods are time consuming and typically take hours to prepare data and hours to run. If the results are not acceptable, the cycle repeats. This paper attempts to present a new approach in using a state-of-the-art business intelligence (BI) tool for solving one subset of the problem which is forecasting the flow of lots in the line using an unconstrained modeling approach. Combined with the power of BI tool with a minimal backend scripting we present an approach that runs a whole fab model for many months in single digit minutes.}, journal={2016 27th Annual SEMI Advanced Semiconductor Manufacturing Conference (ASMC)}, author={Pazhani, Subramaniam and Chakravarthi, Madan and Adhikari, Diwas}, year={2016}, month={May} }
 @article{throughput optimization for queue time constraint zones_2016, year={2016}, month={Jan} }
 @inbook{rienkhemaniyom_pazhani_2015, title={A Supply Chain Network Design Considering Network Density}, booktitle={Toward Sustainable Operations of Supply Chain and Logistics Systems}, publisher={Springer International Publishing}, author={Rienkhemaniyom, Kanokporn and Pazhani, Subramanian}, year={2015}, pages={3–20} }
 @inproceedings{rienkhemaniyom_subramanian_2015, title={A Supply Chain Network Design Considering Network Density}, booktitle={The Proceedings of the 10th International Congress on Logistics and SCM Systems}, author={Rienkhemaniyom, K. and Subramanian, P.}, year={2015} }
 @article{ventura_pazhani_mendoza_2015, title={Finding optimal dwell points for automated guided vehicles in general guide-path layouts}, volume={170}, ISSN={0925-5273}, url={http://dx.doi.org/10.1016/j.ijpe.2015.03.007}, DOI={10.1016/j.ijpe.2015.03.007}, abstractNote={The dwell points for idle vehicles in an automated guided vehicle (AGV) system determine the response times for pick-up requests and thus affect the performance of automated manufacturing systems. In this paper, we address the problem of optimally locating dwell points for a given number of AGVs in a general guide-path layout. Based on an optimality property, we propose new mixed integer linear programming (MILP) formulations for three versions of the problem: (i) minimizing the mean response time in the system, (ii) minimizing the maximum response time in the system, and (iii) minimizing the maximum response time in the system considering time restrictions on vehicle availability. Given that the computational time required to solve the MILP models significantly increases with the size of the guide-path network and number of available AGVs, we also develop a generic genetic algorithm (GA) that can be applied to all three versions of the problem. A computational study is carried out on the single-loop layout and two special cases of two-dimensional grid networks with the objectives of minimizing mean response time and minimizing the maximum response time. The results show that the proposed GA procedure can yield optimal or near optimal solutions in reasonable time.}, journal={International Journal of Production Economics}, publisher={Elsevier BV}, author={Ventura, José A. and Pazhani, Subramanian and Mendoza, Abraham}, year={2015}, month={Dec}, pages={850–861} }
 @article{ravindran_portillo_solo_cintrón_bastian_griffin_rienkhemaniyom_pazhani_wadhwa_bilsel_et al._2015, title={Multiple Criteria Decision Making in Supply Chain Management}, publisher={CRC Press}, author={Ravindran, A Ravi and Portillo, Rodolfo C and Solo, Christopher J and Cintrón, Aixa L and Bastian, Nathaniel D and Griffin, Paul M and Rienkhemaniyom, Kanokporn and Pazhani, Subramanian and Wadhwa, Vijay and Bilsel, R Ufuk and et al.}, year={2015} }
 @inproceedings{rienkhemaniyom_subramanian_janjarassuk_2015, title={Vulnerability assessment in supply chain network design}, booktitle={The Proceedings of the 16th Asia Pacific Industrial Engineering and Management Systems Conference}, author={Rienkhemaniyom, K. and Subramanian, P. and Janjarassuk, Udom}, year={2015} }
 @article{pazhani_ravindran_2014, title={Design of Closed Loop Supply Chain Networks}, volume={1}, ISSN={2334-4547 2334-4555}, url={http://dx.doi.org/10.4018/ijban.2014010104}, DOI={10.4018/ijban.2014010104}, abstractNote={Given the importance of operating and managing forward and reverse supply chains in an integrated manner, this article considers an integrated four-stage supply chain network with forward and reverse product flows. We consider a closed loop supply chain (CLSC) network with primarily commercial returns, which could be potentially recovered by light repair operations or by refurbishing. The annual estimate of commercial returns in the United States is in excess of $100 billion. This paper discusses the optimal design of a CLSC network.A mixed integer linear programming (MILP) model is developed to determine the optimal locations of the facilities and the distribution of flows between facilities in the CLSC to maximize the total profit. The model is illustrated using a realistic example applicable to the electronics industries. Even though recycling and refurbishing add cost, the overall supply chain profit increases due to a reduction in the raw material cost. Sensitivity analysis is carried out to determine the effect of return percentage and varying demands of customers who are willing to buy refurbished products. The analysis show that the total supply chain profit increases with the increase in refurbishing activity. Finally, changes in the network design with respect to the uncertainty in these return parameters are also studied. The results show that the changes in return parameters lead to changes in optimal network design implying the need to explicitly consider the uncertainty in these return parameters.}, number={1}, journal={International Journal of Business Analytics}, publisher={IGI Global}, author={Pazhani, Subramanian and Ravindran, A. Ravi}, year={2014}, month={Jan}, pages={43–66} }
 @inproceedings{pazhani_ventura_mendoza_2014, title={Positioning Automated Guided Vehicles in a General Guide-Path Layout}, booktitle={IIE Annual Conference. Proceedings}, author={Pazhani, Subramanian and Ventura, José A and Mendoza, Abraham}, year={2014}, pages={1723} }
 @inproceedings{mendoza_ventura_subramanian_2014, title={Positioning Automated Guided Vehicles in a General Guide-Path Layout,}, booktitle={13th International Material Handling Research Colloquium, Cincinnati, Ohio, USA}, author={Mendoza, A and Ventura, Jose and Subramanian, Pazhani}, year={2014} }
 @inproceedings{positioning automated guided vehicles in a general guide-path layout_2014, booktitle={IIE Annual Conference and Expo 2014}, year={2014}, month={Jan} }
 @article{pazhani_ramkumar_narendran_ganesh_2013, title={A bi-objective network design model for multi-period, multi-product closed-loop supply chain}, volume={30}, ISSN={2168-1015 2168-1023}, url={http://dx.doi.org/10.1080/21681015.2013.830648}, DOI={10.1080/21681015.2013.830648}, abstractNote={Concerns over environmental degradation legislative requirements and growing business needs have fueled the growth of closed-loop supply chains (CLSCs). This paper addresses a bi-objective network design problem for multi-period, multi-product CLSC to minimize the total supply chain costs and to maximize the service efficiency of the warehouses and hybrid facilities. We develop a bi-objective mixed integer linear programming model to assist decisions in (1) location/operating decisions for warehouses, hybrid facilities and manufacturing facilities and (2) production and distribution of products between stages in the supply chain. Goal programming models and compromise programming techniques are used to solve the problem. An application of the model is demonstrated using a case study from the literature.}, number={4}, journal={Journal of Industrial and Production Engineering}, publisher={Informa UK Limited}, author={Pazhani, Subramanian and Ramkumar, N. and Narendran, T.T. and Ganesh, K.}, year={2013}, month={Jun}, pages={264–280} }
 @article{ramkumar_subramanian_narendran_ganesh_2013, title={An Approach for Setting Inventory Norms for a Two-Echelon Supply Chain}, volume={6}, ISSN={1935-5726 1935-5734}, url={http://dx.doi.org/10.4018/ijisscm.2013100106}, DOI={10.4018/ijisscm.2013100106}, abstractNote={Managing inventories is crucial to the objective of minimizing supply chain costs. This paper presents an approach for setting inventory norms in context of a real-life case of an industry which practices Vendor Managed Inventory (VMI). The role of warehouses and the inventories held by them becomes significant in such an environment. This paper presents a two-phase approach to determine various components of inventory norms taking into account lead time and demand variability. Innovative strategic product classification has been done to decide upon stocking quantity at warehouses.}, number={4}, journal={International Journal of Information Systems and Supply Chain Management}, publisher={IGI Global}, author={Ramkumar, N. and Subramanian, P. and Narendran, T. T. and Ganesh, K.}, year={2013}, month={Oct}, pages={102–119} }
 @inproceedings{pazhani_ravindran_2013, title={Design of Closed Loop Supply Chain Networks}, booktitle={IIE Annual Conference. Proceedings}, author={Pazhani, Subramanian and Ravindran, A. Ravi}, year={2013} }
 @inproceedings{pazhani_ventura_mendoza_2013, title={Optimizing Inventory Levels in a Serial Supply Chain considering Multiple Suppliers and Transportation Costs}, booktitle={IIE Annual Conference}, author={Pazhani, Subramanian and Ventura, José A and Mendoza, Abraham.}, year={2013}, pages={3994–4002} }
 @article{subramanian_ramkumar_narendran_ganesh_2013, title={PRISM: PRIority based SiMulated annealing for a closed loop supply chain network design problem}, volume={13}, ISSN={1568-4946}, url={http://dx.doi.org/10.1016/j.asoc.2012.10.004}, DOI={10.1016/j.asoc.2012.10.004}, abstractNote={Concerns over environmental degradation, legislative requirements and growing needs of business have fueled the growth of Closed Loop Supply Chains (CLSC). We consider a CLSC and address the issues of designing the network and of optimizing the distribution. Four variants of the problem are considered. The problem is modeled as an Integer Linear Program (ILP). We develop a constructive heuristic based on Vogel's approximation method–total opportunity cost method to provide good initial solutions to a priority-based simulated annealing heuristic, to accelerate its convergence. Trials on a set of hypothetical datasets have yielded encouraging results. The methodology is also tested using a case study data of a company producing electronic products. Implications for sustainability are discussed.}, number={2}, journal={Applied Soft Computing}, publisher={Elsevier BV}, author={Subramanian, P. and Ramkumar, N. and Narendran, T.T. and Ganesh, K.}, year={2013}, month={Feb}, pages={1121–1135} }
 @inproceedings{ramkumar_pazhani_narendran_ganesh_2013, title={Three Phase Heuristics for Inventory Routing Problem}, booktitle={IIE Annual Conference. Proceedings}, author={Ramkumar, N. and Pazhani, S. and Narendran, T. T. and Ganesh, K.}, year={2013}, pages={4003} }
 @article{subramanian_ramkumar_narendran_ganesh_2012, title={A technical note on ‘Analysis of closed loop supply chain using genetic algorithm and particle swarm optimisation’}, volume={50}, ISSN={0020-7543 1366-588X}, url={http://dx.doi.org/10.1080/00207543.2011.593348}, DOI={10.1080/00207543.2011.593348}, abstractNote={This study analyses the mixed-integer linear program (MILP) proposed by Kannan et al. [Kannan, G., Noorul Hag, A., and Devika, M., 2009. Analysis of closed loop supply chain using genetic algorithm and particle swarm optimization. International Journal of Production Research, 47 (5), 1175–1200] in their paper entitled ‘Analysis of closed loop supply chain using genetic algorithm and particle swarm optimisation’. Since we find inconsistencies in the model, we propose modifications to rectify the flaws. The revised model is presented and tested using a hypothetical problem.}, number={2}, journal={International Journal of Production Research}, publisher={Informa UK Limited}, author={Subramanian, P. and Ramkumar, N. and Narendran, T.T. and Ganesh, K.}, year={2012}, month={Jan}, pages={593–602} }
 @article{ramkumar_subramanian_narendran_ganesh_2012, title={Mixed integer linear programming model for multi-commodity multi-depot inventory routing problem}, volume={49}, ISSN={0030-3887 0975-0320}, url={http://dx.doi.org/10.1007/s12597-012-0087-0}, DOI={10.1007/s12597-012-0087-0}, number={4}, journal={OPSEARCH}, publisher={Springer Science and Business Media LLC}, author={Ramkumar, N. and Subramanian, P. and Narendran, T. T. and Ganesh, K.}, year={2012}, month={May}, pages={413–429} }
 @article{ramkumar_subramanian_narendran_ganesh_2011, title={A hybrid heuristic for inventory routing problem}, volume={1}, ISSN={1742-6952 1742-6960}, url={http://dx.doi.org/10.1504/ijet.2011.043113}, DOI={10.1504/ijet.2011.043113}, abstractNote={This paper addresses an inventory routing problem in vendor managed inventory systems with explicit consideration of buffer stock levels at warehouses. The problem involves a manufacturer delivering a product to a set of warehouses with available fleet capacity with the objective of minimising transportation and inventory costs. We have developed an integer linear programme (ILP) and proposed a hybrid heuristic for the problem. In the proposed heuristic, inventory is allocated using an ILP, vehicles are allotted to customers on the basis of proximity and routes for vehicles are determined using simulated annealing. The proposed heuristic is validated with different datasets and found to be performing well.}, number={1}, journal={International Journal of Electronic Transport}, publisher={Inderscience Publishers}, author={Ramkumar, N. and Subramanian, P. and Narendran, T.T. and Ganesh, K.}, year={2011}, pages={45} }
 @article{ramkumar_subramanian_narendran_ganesh_2011, title={Erratum to “A genetic algorithm approach for solving a closed loop supply chain model: A case of battery recycling” [Appl. Math. Modell. 34 (2010) 655–670]}, volume={35}, ISSN={0307-904X}, url={http://dx.doi.org/10.1016/j.apm.2011.05.026}, DOI={10.1016/j.apm.2011.05.026}, abstractNote={This study analyzes Mixed Integer Linear Program (MILP) proposed by G. Kannan, P. Sasikumar M. Devika, (2010) in their paper titled 'A genetic algorithm approach for solving a closed loop supply chain model: A case of battery recycling', Applied Mathematical Modelling, (34, 655–670). The model in Kannan et al. (2010) is found to be inadequate for the problem described. It is erroneous/infeasible in terms of constraints, objective and variables. In this work, we list down the flaws in the published work and propose modifications to rectify the flaws. The revised model is presented and illustrated using hypothetical problems.}, number={12}, journal={Applied Mathematical Modelling}, publisher={Elsevier BV}, author={Ramkumar, N. and Subramanian, P. and Narendran, T.T. and Ganesh, K.}, year={2011}, month={Dec}, pages={5921–5932} }
 @article{rangwani_subramanian_ramkumar_narendran_2011, title={Heuristic for a single period single product closed loop supply chain}, volume={4}, ISSN={1748-1252 1748-1260}, url={http://dx.doi.org/10.1504/ijenm.2011.041159}, DOI={10.1504/ijenm.2011.041159}, abstractNote={This paper addresses a single period, single product closed loop supply chain (CLSC) allocation problem. We propose an integer linear programming (ILP) model and a progressive constructive heuristics based on Vogel's approximation method-total opportunity cost (VAM-TOC) method. Trials on a number of datasets have yielded encouraging results.}, number={3}, journal={International Journal of Enterprise Network Management}, publisher={Inderscience Publishers}, author={Rangwani, Neelesh and Subramanian, P. and Ramkumar, N. and Narendran, T.T.}, year={2011}, pages={311} }
 @inproceedings{subramanian_narendran_ganesh_2010, title={A Multi Objective Network Design Model for Single Period, Multi Product Closed Loop Supply Chain}, booktitle={43rd Annual Convention of Operational Research Society of India, Madurai}, author={Subramanian, P and Narendran, T.T and Ganesh, K}, year={2010} }
 @inproceedings{subramanian_p_2010, title={A Simulation Study on the Performance of Load Selection rules for Multiple-Load Automated Guided Vehicles}, booktitle={International Conference on Advances in Industrial Engineering Applications, Anna University, Chennai}, author={Subramanian, P. Shahabudeen and P}, year={2010} }
 @article{subramanian_ramkumar_narendran_2010, title={Mathematical model for multi-echelon, multi-product, single time-period closed loop supply chain}, volume={2}, ISSN={1758-9401 1758-941X}, url={http://dx.doi.org/10.1504/ijbpscm.2010.036200}, DOI={10.1504/ijbpscm.2010.036200}, abstractNote={Closed-loop supply chain (CLSC) management becomes relevant today in the context of environmental degradation. This paper addresses the problem from a typical business perspective and seeks to minimise the total supply chain costs. Most of the CLSC models examined in the current literature are case-specific. In this study, the integration of forward and reverse logistics is investigated. A generalised multi-echelon, single time-period, multi-product, closed loop supply chain is formulated as an integer linear programme (ILP). This model is intended to aid decision-making on issues such as material procurement, production, distribution, recycling and disposal of end-of-life (EOL) items. It also helps in the selection of locations of number of manufacturers, of distribution centres, of disposal sites and of recycling plants with the respective operation units and demand.}, number={3/4}, journal={International Journal of Business Performance and Supply Chain Modelling}, publisher={Inderscience Publishers}, author={Subramanian, P. and Ramkumar, N. and Narendran, T.T.}, year={2010}, pages={216} }
 @article{mathematical model for multi-echelon, multi-product, single time-period closed loop supply chain_2010, url={https://www.inderscienceonline.com/doi/abs/10.1504/IJBPSCM.2010.0362}, DOI={10.1504/IJBPSCM.2010.0362}, journal={International Journal of Business Performance and Supply Chain Modelling}, year={2010}, month={Nov} }
 @article{ramkumar_subramanian_rajmohan_2009, title={A multi-criteria decision making model for outsourcing inbound logistics of an automotive industry using the AHP and TOPSIS}, volume={3}, ISSN={1748-1252 1748-1260}, url={http://dx.doi.org/10.1504/ijenm.2009.032396}, DOI={10.1504/ijenm.2009.032396}, abstractNote={This paper focuses on the inbound logistics segment in the supply chain of automobile companies, which are known to be highly complex. This has always affected key business functions in the supply chain with respect to cost, coordination, and material delay issues. During third party logistics service provider (TPLs) selection, practitioners have started to concentrate on coordination, integration, and cooperation as some of the key areas to improve SC performance. In this context, we propose a model for selection of TPLs network with an objective to create a favourable environment for improving coordination and integration using analytic hierarchy process (AHP) and technique for order preference by similarity to ideal situation (TOPSIS) approach. A case of an automobile company is used to explain the model and potential expected benefits are discussed. A comparative analysis on decision-making certainty between the classical AHP and TOPSIS approach is also discussed.}, number={3}, journal={International Journal of Enterprise Network Management}, publisher={Inderscience Publishers}, author={Ramkumar, N. and Subramanian, P. and Rajmohan, M.}, year={2009}, pages={223} }
 @inproceedings{subramanian_ramkumar_narendran_2009, title={Mathematical model for Multi-Echelon, Multi-Product, Single Time-Period Closed Loop Supply Chain}, booktitle={XIII Annual International Conference of Society of Operations Management, IIT Madras}, author={Subramanian, P and Ramkumar, N and Narendran, T.T.}, year={2009} }
 @inproceedings{subramanian_narendran_karthick_2008, title={Selection of Third party logistics service provider in inbound logistics of SCM using AHP}, booktitle={4th International conference on Logistics and Supply Chain Management, PSG college of Technology, Coimbatore}, author={Subramanian, P and Narendran, T.S. and Karthick, C.}, year={2008} }