In this paper, a two stages method to determine suitable benchmark and return scale of the decision making units set is presented. At first, all of the efficient reference set in no radial data envelopment analysis (DEA) based on linear programming is found. first, RAM model is introduced and units is investigated using this model, then, to run the given algorithm below steps is performed. At t...

fuzzy linear regression models are used to obtain an appropriate linear relation between a dependent variable and several independent variables in a fuzzy environment. several methods for evaluating fuzzy coefficients in linear regression models have been proposed. the first attempts at estimating the parameters of a fuzzy regression model used mathematical programming methods. in this the...

introduction: most of iran’s health budget goes to hospitals as the largest care providing unit in the community. more than 60% of hospital resources are allocated for staffing. one of the problems facing hospitals especially in critical and sensitive parts such as in emergency room is appropriate staffing. this research was designed to investigate and improve nursing staffing and human resourc...

quality of products and services is considered as a key factor for customer satisfaction. quality function deployment (qfd) is known as a critical tool for translating voice of customers to prioritize technical requirements of a production. the level of this satisfaction depends on the number of fulfilled requirements. it should be noted that this level varies according to the possible constrai...

much research hasn’t been done in the area of project selection in the public sector. in this paper, we tried to choose projects in the public sector, and a linear programming model is presented. in an effort to build the model, the decision criteria were identified using the delphi method and then the criteria were reviewed at conceptual combining. the model was constructed in a linear, goal a...

this paper is about discrete sensitivity analysis. a triangular bending element with constant moment and six degrees of freedom is used. the required derivatives for sensitivity analysis are calculated explicitly. these formulations, finite element method and sequential linear programming are utilized to find shape optimization of plate bending structures. the numerical examples, which show the...

Presented here is a generalization of the implicit enumeration algorithm that can be applied when the objec-tive function is being maximized and can be rewritten as the difference of two non-decreasing functions. Also developed is a computational algorithm, named linear speedup, to use whatever explicit linear constraints are present to speedup the search for a solution. The method is easy to u...