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This paper presents an approach to modelling fracture networks in hot dry rock geothermal reservoirs. A detailed understanding of the fracture network within a geothermal reservoir is critically important for assessments of reservoir potential and optimal production design. One important step in fracture network modelling is to estimate the fracture density and the fracture geometries, particularly the size and orientation of fractures. As fracture networks in these reservoirs can never be directly observed there is significant uncertainty about their true nature and the only feasible approach to modelling is a stochastic one. We propose a global optimization approach using simulated annealing which is an extension of our previous work. The fracture model consists of a number of individual fractures represented by ellipses passing through the micro-seismic points detected during the fracture stimulation process, i.e. the fracture model is conditioned on the seismic points. The distances of the seismic points from fitted fracture planes (ellipses) are, therefore, important in assessing the goodness-of-fit of the model. Our aims in the proposed approach are to formulate an appropriate objective function for the optimal fitting of a set of fracture planes to the micro-seismic data and to derive an efficient modification scheme to update the model parameters. The proposed objective function consists of three components: orthogonal projection distances of the seismic points from the nearest fitted fractures, the amount of fracturing (fitted fracture areas) and the volumes of the convex hull of the associated points of fitted fractures. The functions used in the model update scheme allow the model to achieve an acceptable fit to the points and to converge to acceptable fitted fracture sizes. These functions include two groups of proposals: one for updating fracture parameters and the other for determining the size of the fracture network. To increase the efficiency of the optimization, a spatial clustering approach, the Distance-Directional Transform, was developed to generate parameters for newly proposed fractures. A simulated dataset was used as an example to evaluate our approach and we compared the results to those derived using our previously published algorithm on a real dataset from the Habanero geothermal field in the Cooper Basin, South Australia. In a real application, such as the Habanero dataset, it is difficult to determine definitively which algorithm performs better due to the many uncertainties but the number of association points, the number of final fractures and the error are three important factors that quantify the effectiveness of our algorithm. [ABSTRACT FROM AUTHOR]

Objective: To compare safety and efficacy of pantoprazol , metoclopramide, ondansetron, as compared to placebo, in controlling gastrointestinal (GI) complaints of thyroid cancer patients treated with I-131these patients., Design: Four-armed, parallel group, single blind, randomized controlled clinical trial, setting: A university hospital, registration: database for clinical trials IRCT2013061713705N1., Patients: 85 patients with differentiated thyroid cancer who received 131I., Main Outcome Measures: Postradioiodine nausea and vomiting within three days of therapy (primary endpoint); occurrence of adverse reaction., Results: The patients' characteristics were similar within the study groups. Among the study variables, age, sex, administered dosage, history of previous GI complaints, and history of hyperemesis gravidarum in female patients were not statistically different among the groups (p > 0.05). The results revealed that only ondansetron shows a therapeutic benefit over the placebo in controlling nausea (p < 0.05); however, it does not prevent vomiting (p > 0.05). The other two drugs, pantoprazole and metoclopramide, did not control nausea (p > 0.05) or vomiting (p > 0.05)., Conclusions: This study may demonstrate that the therapeutic dose of ondansetron could be an effective prophylactic agent in controlling GI complaints in differential thyroid carcinoma (DTC) patients following RAI therapy; however, these preliminary findings should be validated in larger studies.