Sharif Digital Repository

Enhancing the quality of the product has always been one considerable concern of production process management, and this subject gave way to implementing so many methods including robust design. In this paper, robust design utilizes response surface methodology (RSM) considering the mean and variance of the response variable regarding system design, parameter design, and tolerance design. In this paper, customer requirements and robust design are regarded simultaneously to achieve enriched quality. Subsequently, with a non-linear programming, a novel method for integrating RSM and quality function deployment has been proposed to achieve robustness in design. The customer requirements are... 

Fuzzy logic is one of the effective tools to handle uncertainty and vagueness in engineering and mathematics. One major part of fuzzy logic is ranking fuzzy numbers. In many fuzzy program systems, ranking fuzzy numbers has a remarkable role in decision making and data analysis. Despite the fact that a variety of methods exists for ranking fuzzy numbers, no one can rank fuzzy numbers perfectly in all cases and situations. In this paper, a new method for ranking fuzzy numbers based on the left and right using distance method and α-cut has been presented. To achieve this, a fuzzy distance measure between two generalized fuzzy numbers is proposed. The new measure is expanded with the help of the... 

Global economic expansion and increasing concentration of people in the large cities, especially in developing countries leads to some environmental issues such as air pollution. Relocation of the firms as a great air pollutant can be an appropriate alternative for diminishing these pollutions. Yet, there is a lack of research about factors precluding firm relocation with respect to decision making factors when determining whether or not to relocate. Thus, the purpose of this case study is to examine firm relocation decision-making factors and to apprehend the role of environment issues in making them using a combination of SWOT matrix and Analytic Hierarchy Process (AHP). The combination... 

This article introduces a green centralized supply chain in a two-stage stochastic programming model using deteriorating products. The model reduces the cost of purchasing, transporting, storing, product recovery and shortages. This cuts down on greenhouse emission related to transportation, product recovery, and recycling programs. On the basis of this, we explore the utilization of the circular economy to the damages that could occur from used products. Furthermore, revenue sharing and quantity discount contracts are examined in the business models between the members of the supply chain and the external manufacturer. Demand is assumed to be uncertain, and scenarios are created to account... 

This article examines a supply chain network that considers both economic and environmental factors. The network faces challenges related to multi-item products and non-homogenous vehicle types with different costs. Additionally, the production process involves multiple energy sources that emit different levels of air pollution. The main objective is to maximise profits while adhering to different carbon policies. To achieve this goal, the paper presents several supply chain models that are compared under different schemes: no carbon policy (basic one), carbon tax policy, carbon emission policy and carbon trading policy. These models were coded and solved to demonstrate their effectiveness... 

Due to the vague nature of fuzzy numbers, ranking them according to their magnitude is an interesting area of fuzzy numbers. For this reason, several techniques have been proposed for ranking them. Each of these techniques has shown non-intuitive results in specific cases. Cheng employed 'distance method' for ranking fuzzy numbers in Ref [3]. Then Chu and Tsao in [5] found another method. In this article, some problems of Cheng distance method is indicated and then a new revised method for ranking fuzzy numbers has been proposed which can avoid problem for ranking fuzzy numbers. The considerable priority of the proposed method is its simplicity and easiness in calculation with distance... 

Ranking fuzzy numbers plays a main role in many applied models, and in particular decision-making procedures. In any proposed method by the other researches some shortcomings may exist. In this paper, a new method for ranking two generalized fuzzy numbers based on Euclidian distance measure is presented. Besides from distance measure, we exploited the deviations of generalized fuzzy numbers. The proposed method is illustrated by some numerical examples and in particular the results of ranking by the proposed method and some common and existing methods for ranking fuzzy sets is compared to verify the advantages of the new approach  

Modeling and analysis of information system vulnerabilities helps us to predict possible attacks to networks using the network configuration and vulnerabilities information. As a fact, exploiting most of vulnerabilities result in access rights alteration. In this paper, we propose a new vulnerability analysis method based on the Take-Grant protection model. We extend the initial Take-Grant model to address the notion of vulnerabilities and introduce the vulnerabilities rewriting rules to specify how the protection state of the system can be changed by exploiting vulnerabilities. Our analysis is based on a bounded polynomial algorithm, which generates the closure of the Take-Grant graph... 

We study the translocation of stiff polymers through a nanopore, driven by the chemical-potential gradient exerted by binding proteins (chaperones) on the trans side of the pore. Bound chaperones prevent backsliding through the pore and, therefore, partially rectify the polymer passage. We show that the sequence of chain monomers with different binding affinity for the chaperones significantly affects the translocation dynamics. In particular, we investigate the effect of the nearest-neighbor adjacency probability of the two monomer types. Depending on the magnitude of the involved binding energies, the translocation speed may either increase or decrease with the adjacency probability. We... 

Combining the advection-diffusion equation approach with Monte Carlo simulations we study chaperone driven polymer translocation of a stiff polymer through a nanopore. We demonstrate that the probability density function of first passage times across the pore depends solely on the Péclet number, a dimensionless parameter comparing drift strength and diffusivity. Moreover it is shown that the characteristic exponent in the power-law dependence of the translocation time on the chain length, a function of the chaperone-polymer binding energy, the chaperone concentration, and the chain length, is also effectively determined by the Péclet number. We investigate the effect of the chaperone size on... 

The amount of rippling in graphene sheets is related to the interactions with the substrate or with the suspending structure. Here, we report on an irreversibility in the response to forces that act on suspended graphene sheets. This may explain why one always observes a ripple structure on suspended graphene. We show that a compression-relaxation mechanism produces static ripples on graphene sheets and determine a peculiar temperature Tc, such that for T