delay in irrigated wheat primary tillage operations causes yield reduction and hidden timeliness cost in fars province. mechanization of primary tillage operations for irrigated wheat in fars province was simulated using system dynamics approach. a part of the model structure was related to the agricultural operations timeliness costs. for the mentioned simulation, causal relations between syst...

In recent years, production of text documents has seen an exponential growth, which is the reason why their proper classification seems necessary for better access. One of the main problems of classifying text documents is working in high-dimensional feature space. Feature Selection (FS) is one of the ways to reduce the number of text attributes. So, working with a great bulk of the feature spa...

this paper seeks to understand the role of the cost of pollution from vehicles fuel in feasibility of cng national plan. optimal control theory is used with two target functions, one with and another without the cost of pollution. model results indicate the high importance of pollution cost in the project feasibility, in such a way that without consideration of that the project will be infeasib...

Cumulative Count of Conforming (CCC) charts are utilized for monitoring the quality characteristics in high-quality processes. Executive cost of control charts is a motivation for researchers to design them with the lowest cost. Usually in most researches, only one objective named cost function is minimized subject to statistical constraints, which is not effective method for economic-statistic...

Sulfonated polyether ether ketone (SPEEK) is categorized in a nonfluorinated aromatic hydrocarbon proton exchange membrane (PEM) group and considered as a suitable substitute for common per-fluorinated membranes, such as Nafion, due to wider operating temperature, less feed gas crossover, and lower cost. Since modeling results in a better understanding of a phenomenon, in this study a dynamic o...

normal 0 false false false en-us x-none ar-sa stereolithography process limits wider applications due to low dimensional accuracy comparing with cnc. to improve accuracy and reduce part distortion, understanding the physics involved in the relationship between the setup input parameters and the part dimensional accuracy is prerequisite. in this paper, a model is proposed to find and optimize im...

At Rolls-Royce, a study determined that manufacturing part cost can be estimated from dimensional data in the part definition. The method appears to be more accurate than mass-based parametric models or process simulation cost models. Additional advantages are: part definition information is causally related to part manufacturing cost; part definition information is easily available during the ...

the paper discusses the location-allocation model for logistic networks and distribution centers through considering uncertain parameters. in real-world cases, demands and transshipment costs change over the period of the time. this may lead to large cost deviation in total cost. scenario based robust optimization approaches are proposed where occurrence probability of each scenario is not know...

background numerous factors have an effect on the accuracy of an impression and resultant cast, and these include: impression material, impression technique, tray selection, impression disinfection, storage time of impression before pouring, stone type used for fabrication of cast. up to now, there has been little research conducted on the effect of contact time of a cast with an impression, on...