a two-dimensional single particle finite element model was used to examine the effects of particle fragmental pattern on the average molecular weights, polymerization rate and particle overheating in heterogeneous ziegler-natta olefin polymerization. a two-site catalyst kinetic mechanism was employed together with a dynamic two-dimensional molecular species in diffusion-reaction equation. the i...

extensive research has been devoted to economic production quantity (epq) problem. however, little atten-tion has been paid to problems where depreciation cost and process quality cost must be considered, simulta-neously. in this paper, we consider the economic production quantity model of minimizing the annual total cost subject to depreciation cost and process quality cost, where depreciation...

aim : this study compared pr and nb in predicting hcv patient costs. the objective of this study was to predict the direct cost of the hcv patient in iran. background : hepatitis c virus (hcv) is a common and expensive infectious disease in iran. cost associated with hcv and its complications has not been well characterized. analysis of cost data is important in providing consistent information...

some considerable damage to steel structures during the hyogo-ken nanbu earthquake occurred. among them, many exposed-type column bases failed in several consistent patterns, such as brittle base plate fracture, excessive bolt elongation, unexpected early bolt failure, and inferior construction work, etc. the lessons from these phenomena led to the need for improved understanding of column base...

sediment flushing of reservoirs is an operational technique, whereby previously accumulated sediments in the reservoirs are hydraulically removed by accelerated flow when the bottom desiltingoutlets of the dam are opened. in this research, the process of sediment flushing is simulated by a three dimensional numerical model in which sediment and flow interaction are reflected in the reservoirs. ...

In this paper, we considered a deterministic inventory model with time-dependent demand and time-varying holding cost where deterioration is time proportional. The model considered here allows for shortages, and the demand is partially backlogged. The model is solved analytically by minimizing the total inventory cost. The result is illustrated with numerical example for the model. The model ca...