This paper presents a new mathematical model for a bi-objective job shop scheduling problem with sequence-dependent setup times that minimizes the weighted mean completion time and the weighted mean tardiness time. For solving this multi-objective model, we develop a fuzzy multi-objective linear programming (FMOLP) model. In this problem, a proposed FMOLP method is applied with respect to the o...

we study the history and recent developments in nonelementarymodel theory focusing on the framework of abstractelementary classes. we discuss the role of syntax and semanticsand the motivation to generalize first order model theory to nonelementaryframeworks and illuminate the study with concrete examplesof classes of models. this first part introduces the main conceps and philosophies anddiscu...

Positive linear systems are frequently used as mathematical models in research areas like biology and economics. The problem to classify all minimal realizations of these systems is treated in this paper. Extensive use is made of the theory of polyhedral cones. Suucient and necessary conditions for the existence of a positive realization are given, but the problem of minimality leads to the fac...

this study tries to codify a proper mathematical model which can be predict the costs of repair and maintaining the tractors as precisely as possible for three common models of tractors in shahid beheshti cultivation firm in andimeshk-ahvaz road of dezfoul. studied tractors include: newhland tm155 tractor which is chosen from the most perfect file of 10 tractor machines and jandier tractor-3140...

in this paper, a mathematical modeling is developed for plastic analysis of planar frames. to this end, the researcher tried to design an optimization model in linear format in order to solve large scale samples. the computational result of cpu time requirement is shown for different samples to prove efficiency of this method for large scale models. the fundamental concept of this model is obta...

In this paper, the common centralized DEA models are extended to the bi-level centralized resource allocation (CRA) models based on revenue efficiency. Based on the Karush–Kuhn–Tucker (KKT) conditions, the bi-level CRA model is reduced to a one-level mathematical program subject to complementarity constraints (MPCC). A recurrent neural network is developed for solving this one-level mathematica...

this paper presents a macro model to predict unreinforced masonry structures in plane behavior. the model is based on the concept of multilaminate theory. in the past, the method has been used to model behavior of soil, disregarding the cohesion and the tensile strength. regarding its mathematical base, and the possibility of applying in other cases, this method is used to predict the ultimate ...

the first purpose of this study is to present an alternative robust model in order to describe ruminal degradation kinetics of forages and to minimize the fitting problems. for this purpose, the korkmaz-uckardes (ku) model, which has a logarithmic structure, was developed. the second purpose of this study is to estimate, by using the korkmaz-uckardes (ku)model, the parameters tp (the time to pr...