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This article will discuss some of the issues in testing 10GBASE-LRM optical interfaces over multimode fiber, and will outline a methodology for doing so. The article will also describe test results from a recent multivendor interoperability test demonstrating the feasibility and robustness of the LRM interface

One of the most serious accidents that can occur in the experimental nuclear fusion reactor ITER is the break of one of the headers of the refrigeration system of the first wall of the Tokamak. This results in water-steam mixture discharge in vacuum vessel (VV), with consequent pressurization of this container. To prevent the pressure in the VV exceeds 150 KPa absolute, a system discharges the steam inside a suppression pool, at an absolute pressure of 4.2 kPa. The computer codes used to analyze such incident (eg. RELAP 5 or MELCOR) are not validated experimentally for such conditions. Therefore, we planned a basic research, in order to have experimental data useful to validate the heat transfer correlations used in these codes. After a thorough literature search on this topic, ACTA, in collaboration with the staff of ITER, defined the experimental matrix and performed the design of the experimental apparatus. For the thermal-hydraulic design of the experiments, we executed a series of calculations by MELCOR. This code, however, was used in an unconventional mode, with the development of models suited respectively to low and high steam flow-rate tests. The article concludes with a discussion of the placement of experimental data within the map featuring the phenomenon characteristics, showing the importance of the new knowledge acquired, particularly in the case of chugging.

The SSN is an emergency system, based on intentional primary depressurization, which, when added to a proven type PWR, has the potential to reduce, by at least a factor of 10, the core melt probability. The paper describes the system components and function. Then it gives a summary of (i) the thermal/hydraulic analyses performed to verify the core cooling capability of the system, and (ii) the probabilistic studies performed for the assessment of the system potential in reducing the core melt probability. The main results of two experimental tests related to the performances of the system are then briefly described. Possible problems faced in the implementation of an SSN concept are discussed in a separate chapter.

The idea to couple the treatment planning system (TPS) to the information on the real boron distribution in the patient acquired by positron emission tomography (PET) is the main added value of the new methodology set-up at DIMNP (Dipartimento di Ingegneria Meccanica, Nucleare e della Produzione) of University of Pisa, in collaboration with the JRC (Joint Research Centre) at Petten (NL). This methodology has been implemented in a new TPS, called Boron Distribution Treatment Planning System (BDTPS), which takes into account the actual boron distribution in the patient's organ, as opposed to other TPSs used in BNCT that assume an ideal uniform boron distribution. BDTPS is based on the Monte Carlo technique and has been experimentally validated comparing the computed main parameters (thermal neutron flux, boron dose, etc.) to those measured during the irradiation of an ad hoc designed phantom (HEterogeneous BOron phantoM, HEBOM). The results are also in good agreement with those obtained by the standard TPS SERA and by reference calculations carried out using an analytical model with the MCNP code. In this paper, the methodology followed for both the experimental and the computational validation of BDTPS is described.

Epidemiological indexes of dental decay and prevalence of Streptococcus mutans in dental plaque were studied in a group of 255 schoolchildren aged 6–11 from a suburban area near Siena (Italy). Mutans streptococci were isolated from 17.4% of subjects: a significant correlation with dental decay indexes and with the presence of active caries was observed.