RESUMO
Hospitals need to identify issues of greater importance on waste management because the implementation of many different strategies may lead to an unconscious increase in costs. Accordingly, the purpose of this study is to define the most effective waste management strategies in the service industry. For this purpose, a novel fuzzy decision-making model is proposed that has two different stages. In this context, six JCI-based indicators are weighted by using sine trigonometric fuzzy Decision Making Trial and Evaluation Laboratory (DEMATEL) methodology. Additionally, a comparative evaluation has also been conducted with sine trigonometric fuzzy Criteria Importance Through Intercriteria Correlation (CRITIC) technique to check the reliability of the findings. On the other hand, five different strategy alternatives are selected by considering the principles of the integrated waste management hierarchy approach. These items are evaluated by considering sine trigonometric fuzzy Technique for Order Preference by Similarity (TOPSIS). On the other side, these factors are also ranked with the help of sine trigonometric fuzzy Additive Ratio Assessment (ARAS) to test the consistency of the results. The main contribution is that prior strategies can be presented to the hospitals to have appropriate waste management process by defining the most important factors. Criteria weighting and alternative ranking results are the same in all combinations. Therefore, it is seen that the proposed model creates coherent and consistent results. It is defined that efficient storage of waste is the key issue to have effective waste management process. Moreover, 'reduce' is found as the most critical stage of this process.
RESUMO
This paper presents a two-dimensional pore-scale network model of a rough-walled fracture whose inner structure had been mapped using x-ray microtomography. The model consists of a rectangular lattice of conceptual pores and throats representing local aperture variations. It is a two-phase model that takes into account capillary, viscous, and gravity forces. Mapping of fluids and fracture topology was done at a voxel resolution of 0.027 x 0.027 x 0.032 mm(3) , which allowed the construction of realistic fracture representations for modeling purposes. This paper describes the necessary data conditioning for network modeling, a different approach to determine advancing and receding contact angles from direct x-ray microtomography scans, and the network model formulation and methods used in the determination of saturation, absolute and relative permeabilities, capillary pressures, and fluid distributions. Direct comparison of modeled results and experimental observations, for both drainage and imbibition processes, is presented in the companion paper [M. Piri and Z. T. Karpyn, following paper, Phys. Rev. E 76, 016316 (2007)].
RESUMO
This paper presents the implementation of the pore-scale network model described in paper I [see preceding paper, Z. T. Karpyn and M. Piri, Phys. Rev. E 76, 016315 (2007)]. The model is used to estimate flow properties and predict fluid occupancy during two-phase flow displacements in a rough-walled fracture. The fracture's inner structure is available from the reconstruction of x-ray microtomography images of a fractured sandstone core. The model is able to represent mechanisms such as pistonlike displacement, cooperative pore filling, and snapoff. We study the effects of aperture map scales, rate of injection, and gravity on the distribution of phases inside the fracture and present successful predictions of fluid occupancy during primary drainage, imbibition, and secondary drainage. Results were validated rigorously against x-ray microtomography scans obtained from two-phase flow experiments [see Z. T. Karpyn, A. S. Grader, and P. M. Halleck, J. Colloid Interface Sci. 307, 181 (2007)] and showed two-phase fluid structures in agreement with experimental observations.
