The study explores the parallel use of fuzzy reasoning to assess better the value of real estate, which has been previously assessed by exponential regression model if parameters of the multiple regression functions are changing discontinuously on the given domain. The results are compared with those obtained using a traditional multiple regression model only. This method is interesting for real estate appraisers, real estate companies, This article describes an effort to design parallel regression-fuzzy system
COBISS.SI-ID: 2145379
In this paper we extend MRP theory in reverse logistics including transportation matrices. Our aim is to demonstrate the versatility obtained from combining input-output analysis and Laplace transforms enabling an analysis of a supply chain including four sub-systems, namely manufacturing, distribution, consumption and reverse logistics, where distance between activity cells in a supply chain play important rôle. The main focus is on reverse logistics (recycling, remanufacturing), as the manufacturing sub-system, so far, has received most attention in the literature. Especially we wish to show, also by numerical example, how to evaluate the displacement of disposal or reverse activities far away from agglomerations, which often means improved environment for nearby inhabitants. Formula for NPV evaluation of reverse activities at transportation time delays from different directions and from many consumption sources including influence of timing and transportation costs of reverse activities have been developed as novelty here. We intend to show that supply chain sub-systems may accurately be described using input and output matrices collected together in corresponding matrices for the system as a whole. Activity levels in each activity cell, governing the speed of the respective processes, in general, will be considered as decision variables. By introducing unit values pertaining to the items in the form of a price vector, the economic performance of the subsystems may be evaluated and locally optimised. On occasion, when possible, we will use the Net Present Value as a measure of this performance. Since we are now giving attention to reverse logistics in which the flows of materials and goods could be also divergent like in distribution part, the recent results on extension of basic MRP theory introducing concepts of output lead time, output transportation delay matrices, and the generalised output matrix have been also introduced in the model of reverse logistics.
COBISS.SI-ID: 2230883
MRP Theory has been developed during the last 25 years for capturing processes concerning multi-level, multi-stage production-inventory systems in a compact way. Input–output analysis has been used to describe structures, and Laplace transforms to describe the timing relations. This theory has mainly dealt with assembly systems, in which each item has only one successor. The lead times for the assembly of an item have usually been constants and equal for all items entering a given successor. For such systems, the equations describing the flows of components may be written to include the generalised input matrix as the product of an input matrix containing needed amounts, and a diagonal lead time matrix with lead time operators along its main diagonal. On occasion, there has been a need to deviate from this representation enabling lead times to vary depending on which input item that is considered. This paper deals with how to represent lead times and similar output delays (in diverging, arborescent systems), when the assumption of equal times is relaxed, in order to retain the basic structure of the fundamental balance equations involved. The intention of this paper is to create a general taxonomy for the representation of timing in algebraic form for a variety of systems covering both assembly systems and arborescent systems (such as extraction, distribution and remanufacturing), as well as systems with mixed properties. For instance, this method may be used directly for the evaluation of investments in capacity or in the location of activities in a production network, or even in a global supply chain. The paper is theoretical base for further research of economic-environmental contingency.
COBISS.SI-ID: 2175075