In this paper we extend and apply MRP theory towards reverse logistics including the considerations of transportation consequences. Our aim is to demonstrate the versatility obtained from using MRP theory when combining Input–Output Analysis and Laplace transforms. This enables an analysis of a supply chain including four sub-systems, namely manufacturing, distribution, consumption and reverse logistics, where the geographical distance between the activities play an important role. The main focus in this paper is on reverse logistics (recycling, remanufacturing). Especially we wish to model the evaluation of disposal and reverse activities far away from agglomerations, which often means an improved environment for nearby inhabitants. This is also illustrated in a numerical example. We use the Net Present Value as a measure of the economic performance.
COBISS.SI-ID: 2230883
Grubbström's well-developed MRP Theory has been mostly used in modeling production processes. Global supply chains also contain distribution, consumption and recycling processes. For this reason theory was recently further extended to incorporate all kinds of activities. Such extended model, which consists of four main sub-systems, is closed and can be used for severaldetailed analyses. Since the importance of reverse logistics is increasing, this paper will focus on parameters which determine Net Present Value of the whole system, depending on geographical location of recycling facilities. We will show how lead times, transportation costs, setup costs andprice of labor and energy of individual location contribute to overall NPV of the system.
COBISS.SI-ID: 2315363
The retirement age of industrial workers in national pension schemes is being raised. However, many industrial workers are not able to work until they have reached the increased retirement age. This problem is decreasing social security, increasing workers anxiety regarding the future and influencing the quality and timing of production processes. Disruptions and lower quality items produced in one activity cell of a supply chain can have a ripple effect throughout an entire supply chain. To solve this problem, we should put in place supplementary occupational pension schemes, which would compensate firms for the depreciated ability of their elderly workers to work when they have reached the previous retirement age but have not yet reached the new, higher retirement age. This article is introduces a model that is based on extended MRP Theory. The model can be used as a basis for negotiations between employers and employees to keep production at the same level of quality. The trade-off between higher contributions to supplementary occupational pension schemes and lower added values is considered. Contributions enable the early retirement of industrial workers at one or more workplaces in a supply chain, while lower added value is the result of lower quality and the perturbed timing of items that are produced in one or more activity cells of a supply chain: these issues have a ripple effect throughout an entire supply chain. The net present value approach is used. THE EXTENDED MRP MODEL FOR THE EVALUATION AND FINANCING OF SUPERANNUATION SCHEMES IN A SUPPLY CHAIN By: Bogataj, David; Vodopivec, Robert; Bogataj, Marija TECHNOLOGICAL AND ECONOMIC DEVELOPMENT OF ECONOMY Volume: 19 Special Issue: SI Supplement: 1 Pages: S119-S133 Published: 2013 Full Text Close AbstractClose Abstract The retirement age of industrial workers in national pension schemes is being raised. However, many industrial workers are not able to work until they have reached the increased retirement age. This problem is decreasing social security, increasing workers anxiety regarding the future and influencing the quality and timing of production processes. Disruptions and lower quality items produced in one activity cell of a supply chain can have a ripple effect throughout an entire supply chain. To solve this problem, we should put in place supplementary occupational pension schemes, which would compensate firms for the depreciated ability of their elderly workers to work when they have reached the previous retirement age but have not yet reached the new, higher retirement age. This article is introduces a model that is based on extended MRP Theory. The model can be used as a basis for negotiations between employers and employees to keep production at the same level of quality. The trade-off between higher contributions to supplementary occupational pension schemes and lower added values is considered. Contributions enable the early retirement of industrial workers at one or more workplaces in a supply chain, while lower added value is the result of lower quality and the perturbed timing of items that are produced in one or more activity cells of a supply chain: these issues have a ripple effect throughout an entire supply chain. The net present value approach is used.
COBISS.SI-ID: 17704754