APPLICATION OF THE EXTENDED MRP THEORY TO A BABY FOOD COMPANY

Actual markets require companies to think about new ways to improve their business or to get additional advantages from their existing competences. Such improvements should not be limited to optimisation of individual activity cells but should be the result of broader analyses. Companies should consider their whole supply chains and make deep observation of dependencies between individual activity cells. Material requirements planning (MRP) Theory has proved to be a successful tool for describing and evaluating multistage, multilevel production systems with the use of Net Present Value (NPV) calculation. Recently, this theory has been extended in a way that it also deals with other vital parts of global supply chains, such as distribution, consumption and the reverse logistics. We call this approach the Extended MRP Theory (EMRP Theory). This paper shows how EMRP Theory can be used in analysing business processes for a Spanish company dedicated to baby food production

the response latency in global production and logistics a trade off between robotization and globalization of a chain

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Net present value evaluation of energy production and consumption in repeated reverse logistics

The paper is based on Grubbström’s MRP theory previously used in analysis of production processes “under one roof ”. This theory has recently been extended to model global supply chains by Bogataj and Grubbström, both scientists from the MEDIFAS faculty. Every production cycle is followed by distribution, consumption and recycling activities. In broad supply chains, transportation costs between pairs of activity cells have a significant impact on the overall net present value of the system. Possible flows inside or between subsystems can all be described with input-output matrices H and G. Recently published papers of the above mentioned authors describe the presentation of supply chains in a generalized form. Generalized input and output matrices H( )s ( and ( )s ( G hold technical coefficients and lead times. Lead times are split into 2 parts: production and transportation. As presented in the publication of R. W. Grubbström, L. Bogataj and M. Bogataj, and further research of these authors, the results of recycling activities in the extended MRP model are the recovered and the waste items, but in their model the recycling of the items is not repeated. Recovered items could be reused several times in future production cycles, reducing the need to purchase new items on the market as considered here. The waste items must be disposed of, requiring environmental taxes which vary among regions, depending on local environmental policy. If recovered, items must be delivered from the recycling facility back to production, and waste items must be sent to landfills. This process requires an expenditure of human resources, and energy at each activity cell plays an important role. In this article we show how the location of recycling facilities, the prices and quantity of energy needed and the environmental taxes can drastically influence the net present value for the entire system. We also present the method for evaluating cases where energy can be recovered during recycling or decomposition processes at landfills. It is also assumed that energy recovery can be stimulated with subsidized purchase prices, but generally, lower quality energy can be expected as an output of these processes. This paper introduces generalized input and output energy matrices, which describe these energy flows and their impact on environmental sustainability through the net present value of the system, which is the novelty in the extended MRP theory. First published online: 17 Sep 201

Master production schedule using robust optimization approaches in an automobile second-tier supplier

[EN] This paper considers a real-world automobile second-tier supplier that manufactures decorative surface finishings of injected parts provided by several suppliers, and which devises its master production schedule by a manual spreadsheet-based procedure. The imprecise production time in this manufacturer's production process is incorporated into a deterministic mathematical programming model to address this problem by two robust optimization approaches. The proposed model and the corresponding robust solution methodology improve production plans by optimizing the production, inventory and backlogging costs, and demonstrate the their feasibility for a realistic master production schedule problem that outperforms the heuristic decision-making procedure currently being applied in the firm under study.Funding was provided by Horizon 2020 Framework Programme (Grant Agreement No. 636909) in the frame of the "Cloud Collaborative Manufacturing Networks" (C2NET) project.Martín, AG.; Díaz-Madroñero Boluda, FM.; Mula, J. (2020). Master production schedule using robust optimization approaches in an automobile second-tier supplier. Central European Journal of Operations Research. 28(1):143-166. https://doi.org/10.1007/s10100-019-00607-2S143166281Alem DJ, Morabito R (2012) Production planning in furniture settings via robust optimization. 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Modeling Industrial Lot Sizing Problems: A Review

In this paper we give an overview of recent developments in the field of modeling single-level dynamic lot sizing problems. The focus of this paper is on the modeling various industrial extensions and not on the solution approaches. The timeliness of such a review stems from the growing industry need to solve more realistic and comprehensive production planning problems. First, several different basic lot sizing problems are defined. Many extensions of these problems have been proposed and the research basically expands in two opposite directions. The first line of research focuses on modeling the operational aspects in more detail. The discussion is organized around five aspects: the set ups, the characteristics of the production process, the inventory, demand side and rolling horizon. The second direction is towards more tactical and strategic models in which the lot sizing problem is a core substructure, such as integrated production-distribution planning or supplier selection. Recent advances in both directions are discussed. Finally, we give some concluding remarks and point out interesting areas for future research

A review of discrete-time optimization models for tactical production planning

This is an Accepted Manuscript of an article published in International Journal of Production Research on 27 Mar 2014, available online: http://doi.org/10.1080/00207543.2014.899721[EN] This study presents a review of optimization models for tactical production planning. The objective of this research is to identify streams and future research directions in this field based on the different classification criteria proposed. The major findings indicate that: (1) the most popular production-planning area is master production scheduling with a big-bucket time-type period; (2) most of the considered limited resources correspond to productive resources and, to a lesser extent, to inventory capacities; (3) the consideration of backlogs, set-up times, parallel machines, overtime capacities and network-type multisite configuration stand out in terms of extensions; (4) the most widely used modelling approach is linear/integer/mixed integer linear programming solved with exact algorithms, such as branch-and-bound, in commercial MIP solvers; (5) CPLEX, C and its variants and Lindo/Lingo are the most popular development tools among solvers, programming languages and modelling languages, respectively; (6) most works perform numerical experiments with random created instances, while a small number of works were validated by real-world data from industrial firms, of which the most popular are sawmills, wood and furniture, automobile and semiconductors and electronic devices.This study has been funded by the Universitat Politècnica de València projects: ‘Material Requirement Planning Fourth Generation (MRPIV)’ (Ref. PAID-05-12) and ‘Quantitative Models for the Design of Socially Responsible Supply Chains under Uncertainty Conditions. Application of Solution Strategies based on Hybrid Metaheuristics’ (PAID-06-12).Díaz-Madroñero Boluda, FM.; Mula, J.; Peidro Payá, D. (2014). A review of discrete-time optimization models for tactical production planning. International Journal of Production Research. 52(17):5171-5205. doi:10.1080/00207543.2014.899721S51715205521

Methodology and tools for improving competence of a chemical plant characterized by a complex Supply Chain network

Supply chain performance is strongly influenced by its design, chosen architecture, logistic network and types of finished product that made their marketplace. Sometimes environmental reasons like site location due to deals between government administration and companies may cause changes in logical design and hence increase logistic network complexity and become in a strategic Supply Chain constraint. Our case study addresses a geographic place of a chemical manufacturing plant inside its supply chain which the 86% of the domestic raw material suppliers, its unique distribution center and 100% of the plastic and metallic packaging suppliers are placed over 800 kilometers of distance. Starting from this restriction the research work consists in how redesign and rethink the architecture of the existing supply chain and optimize the processes inside the chemical plant trying to minimize the cost disadvantages related directly to the physical location of the factory. This research treats the selection of coordination and collaborative mechanisms between supply chain members, other company departments and outsourcing partners in order to create a collaborative coordinated model for optimization of this complex supply chain network. Besides this environment limitation, the most salient threats were internal at the company and consisted successfully implement coordinated actions to improve the management of processes and to take practical level. Fighting against the cultural change of the sectors involved and achieves the proposed expected results. The thesis consists of five practical cases studies of coordinated process for performance improvement. Each one being part of an integrated system that converges in a Plant performance common goal, which is increase supply chain competence. RQ1 tries to identify the processes which will be possible to apply the SC new model and management system emerged from the theoretical study and practical benchmarking cases. The research design is then presented by the implementation at Plant’s field level of the proposed develop scheme using the coordinated collaborative improvement model. RQ2 asks whether the chosen cases are adequate. Selecting the best alternative proposed for each thread. After that, the obtained results are presented and discussed for each field case. The focus of the research study is on supply chain practice and supply chain theoretical framework also. To conclude with the author experience that remarks supply chain practice has been heavily influenced by supply chain research and vice versa

A collaborative framework for feasibility analysis in automotive product development with global supply chain

In the competitive world, time to market, new technology and innovation are the measures of the performance of New Product Development (NPD). Companies tend to use a conventional approach to NPD by assigning representatives from their own support functions to review and recommend changes as projects evolve. In recent years, this approach has been questioned since it is a costly and time-consuming approach due to its iterative nature. Researchers argue that the time to market process and the cost of NPD can be reduced considerably by involving the support functions of the supply chain to a greater extent and also earlier in the NPD process. There is a potential industrial requirement for a collaborative framework that facilitates the linkage between Supply Chain Management (SCM) and New Product Development (NPD). This research project focuses on the early stages of the collaborative product development process in the extended enterprise. The research output includes the functional requirements of a framework and a developed prototype methodology with tools and technologies that are tested from case studies within industry. The research also introduces the development and analysis of the framework that allows the integration of the flow of product development related activities within original equipment manufacturers (OEM) and suppliers providing future business benefits. An industrial investigation of an OEM in the automotive industry within the research identified that there are different decision making points in product development and manufacturing. The proposed methodology and framework use key drives to predict and quantify its impact on four main criteria namely: feasibility, time, cost and capability that support or advise on key decision making of OEM’s product development and management process

Optimising the material distribution process for the southern region of Telkom SA

Most government owned telecommunication operators across the world have to deal with a number of regulatory, technology and service challenges, as the industry is liberalised in co-ordinance with worldwide trends. Telkom SA will be facing a number of strategic challenges that will test its ability to survive as a telecommunications company over the next number of years. To remain competitive, Telkom must develop strategies to assure survival in a competitive environment. To assure the long-term survival of Telkom SA when moving into a competitive environment, the organisation must build a sustainable competitive advantage. In the face of increasingly fierce competition, the adoption of collaborative alliances between firms is becoming more and more common and the adoption of a world-class supply chain will be an ideal scenario for Telkom SA. A worldclass supply chain goes beyond the scope of the internal operations of an organisation, therefore the material distribution process was chosen for this study, which involved the internal operations in the organisation. The study included the availability of material up to the transportation of the material to the staging areas. The aim of this research was to identify the inefficiencies of the material distribution process of the Southern Region of Telkom SA to become worldclass. A quantitative technique was used to identify the inefficiencies. It was found that the availability and transportation of material were the inefficient categories, preventing the customer to receive the product or service on time. Communication, inaccurate forecasting and inefficient transportation of material were some of the reasons for not delivering material on time. Some of the recommendations included developing a model that could overcome the current inefficiencies in transportation, improving the communication channels, training and the development of employees at all levels

Exploratory research into supply chain voids within Welsh priority business sectors

The paper reports the findings resulting from the initial stages of an exploratory investigation into Supply Chain Voids (SCV) in Wales. The research forms the foundations of a PhD thesis which is framed within the sectors designated as important by the Welsh Assembly Government (WAG) and indicates local supplier capability voids within their supply chains. This paper covers the stages of initial data gathering, analysis and results identified between June 2006 and April 2007, whilst addressing the first of four research questions. Finally, the approach to address future research is identified in order to explain how the PhD is to progress