This paper proposes a fuzzy multi-objective integer linear programming approach to model a material requirement planning (MRP) problem with fuzzy lead times. We incorporate to the crisp MRP model the possibility of occurrence of each one of the possible lead times. Then, an objective function that maximizes the possibility of occurrence of the lead times is considered. By combining this objecti...

Recognizing the activities performed by the user in an unobtrusive manner is one of the important requisites of pervasive computing. Users perform a number of activities during their day to day life. Tracking and deciding what a user is doing at a given time involves a number of challenges. The lack of a precise pattern in doing an activity at different times is one among them. The number, orde...

An overview of some fuzzy set-based approaches to scheduling is proposed, emphasizing two distinct uses of fuzzy sets: representing preference profiles and modelling uncertainty distributions. The first setting leads to a valued, noncompensatory generalization of constraint-directed scheduling. The other setting yields a possibility-theoretic counterpart of PERT, where probability distributions...

The problem of Order Acceptance and Scheduling (OAS) is defined as a joint decision of which orders to accept for processing and how to schedule them. Any linear programming model representing real-world situation involves the parameters defined by the decision maker in an uncertain way or by means of language statement. Fuzzy data can be used to incorporate vagueness in the real-life situation...

This paper presents a fuzzy extension of the simple assembly line balancing problem of type 2 (SALBP-2) with fuzzy job processing times since uncertainty, variability, and imprecision are often occurred in real-world production systems. The jobs processing times are formulated by triangular fuzzy membership functions. The total fuzzy cost function is formulated as the weighted-sum of two bi-cri...

The development of life time analysis started back in the $20^{textit{th}}$ century and since then comprehensive developments have been made to model life time data efficiently. Recent development in measurements shows that all continuous measurements can not be measured as precise numbers but they are more or less fuzzy. Life time is also a continuous phenomenon, and has already been shown tha...

Using alternative fuel vehicles is one of the ways to reduce the consumption of fossil fuels which have many negative environmental effects. An alternative fuel vehicle needs special planning for its refueling operations because of some reasons, e.g. limited number of refueling stations, uncertain refueling queue times in the stations, variable alternative fuel prices among the stations, etc. I...

A new sterically hindered isoindoline-based 1,3-bis(51-methyl-41-phenyl-21-thiazolylimino)isoindoline (1) was synthesized by fusion method with satisfyingly good yield. The structure of the newly synthesized compound was identified by FT-IR, UV-Vis, 1H-NMR, 13C-NMR and X-ray analysis.

How to model traveler’s perception of travel time is always an important issue in the development of traffic assignment models. Since travelers rarely have perfect knowledge of the road network or of the traveling conditions, they choose routes based on their perceived travel times. Traditionally, travelers’ perceived travel times are treated as random variables, leading to the stochastic traff...

The accuracy of a standard market receiver GPS (Global Positioning System) is near 10-15 meters the 95% of the times. To reach a sub-metric level of accuracy some techniques must be used [1]. This article describes some of these procedures to improve the positioning accuracy by using a low-cost GPS in a differential relative positioning way. The proposed techniques are some variations of Kalman...