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The thermal-hydraulic behavior of complex, large-scale systems such as nuclear reactors is the product of a wide range of fluid-mechanics phenomena. In principle, these phenomena can be modeled directly (at least for single-phase flows) through the direct simulation of the Navier-Stokes equations. However, such a “reactor-scale” direct simulation approach remains infeasible today, given that such a model would need to span a range of scales. Where code developments up to today focused on resolving issues at a specific scale, challenges in which complex phenomena at various scales interact require a different approach. Some system thermal-hydraulic codes nowadays allow three-dimensional modeling. However, computational fluid dynamics codes are superior to that respect. On the other hand, such codes are computationally too expensive to allow modeling a complete system. To overcome this problem, different codes covering multiple scales can be coupled in a multiscale simulation approach. This chapter introduces this multiscale simulation concept, presents modeling choices to be made, explains the challenges, and provides guidelines. Finally, some examples of application of such approaches are shown.

BACKGROUND: Currently, there is no specific pharmacological therapy with established efficacy for the treatment of cocaine dependence. The aim of this study was to determine the safety, tolerability and the effects of aripiprazole and ropinirole in patients with cocaine dependence. METHODS: This randomized clinical trial of 12-week duration was carried out on 28 consecutive patients with cocaine dependence presenting for treatment. The diagnostic assessment was performed using ICD-9-CM criteria and Mini International Neuropsychiatric Interview. The Clinical Global Impression Scale, a Visual Analogue Scale to assess craving and a self-report questionnaire on the use of cocaine were administered at baseline and then weekly throughout the study. Urinalyses were carried out three times per weeks to search for benzoylecgonine. RESULTS: Of the 28 study participants, 14 completed the protocol. Treatment discontinuation was unrelated with side effects. One patient required a dosage reduction of ropinirole because of sleepiness and one patient assigned to aripiprazole who reported moderate akathysia had the dosage reduced to 5 mg/day. Routine blood works did not show significant changes from baseline and the overall proportion of positive urinalyses for benzoylecgnonine did not differ significantly between treatments. Using linear mixed-effect models a significant decrease in craving was found in the overall sample (p

An introduction to the major business organizational options open to small-scale hydroelectric (SSH) projects is given. The major federal income tax treatments of these options are compared. Significant general federal income tax factors affecting SSH projects are reintroduced and explained. Some of the special federal income tax problem areas in SSH development are isolated. Tax benefit flow through or transfer mechanisms are discussed. Tax exempt financing opportunities for private SSH projects are reviewed. (MHR)