Neutronic characterization of the MEGAPIE target

The MEGAPIE project aimed to design, build and operate a liquid metal spallation neutron target of about 1 MW beam power in the SINQ facility at the Paul Scherrer Institut (Villigen, Switzerland). This project is an important step in the roadmap towards the demonstration of the accelerator driven system (ADS) concept and high power liquid metal targets in general. Following the design phase, an experimental program was defined to provide a complete characterization of the facility by performing a “mapping” of the neutron flux at different points, from the center of the target to the beam lines. The neutronic performance of the target was studied using different experimental techniques with the goals of validating the Monte Carlo codes used in the design of the target; additionally, the performance was compared with the solid lead targets used before and after the MEGAPIE experiment.     

ITER CODAC interface for the visible and infra-red wide angle viewing cameras

The amount of data generated by the infra-red and visible cameras at ITER is expected to be considerably larger than most diagnostics. ITER will have 12 infra-red cameras plus 12 visible cameras in four different equatorial port plugs. Each of the ports will have a Plant System Host (PSH) that will provide a standard image of the plant system to the ITER's Control and Data Access and Communication (CODAC) system.The two key functions of these cameras will be the scientific exploitation with the detection of interesting physics events and the operational protection of the machine, namely the first wall. Already assuming high bandwidth requirements for both audio and video, ITER will provide a separate network for this kind of communication, which will be used to transmit both the experimental and informational data provided by the cameras.This paper presents the current camera plant system design and its interaction with ITER CODAC system and networks. Starting from the camera specifications several alternatives for data collection and compression are discussed. The required inputs from CODAC and a first specification for the internal finite state machine are also presented. Finally, a possible hardware straw man design solution for the plant system hardware is proposed.     

Combining audio and video metrics to assess audio-visual quality

Multimedia Tools and Applications - In this work, we studied the use of combination models to integrate audio and video quality estimates to predict the overall audio-visual quality. More...     

The role of user requirements in data repository design

International Journal on Software Tools for Technology Transfer - Requirements engineering plays a crucial role in the development process of an information system as it aims at providing a...     

Finite difference transmission line model for the design of safe multi-section cables in MRI

Magnetic Resonance Materials in Physics, Biology and Medicine - To show the relevance of a simple finite difference transmission line model to help design safe implanted cables in 1.5T MRI’s...     

Inverse wave field extrapolation: a different NDI approach to imaging defects

Nondestructive inspection (NDI) based on ultrasound is widely used. A relatively recent development for industrial applications is the use of ultrasonic array technology. Here, ultrasonic beams generated by array transducers are controlled by a computer. This makes the use of arrays more flexible than conventional single-element transducers. However, the inspection techniques have principally remained unchanged. As a consequence, the properties of these techniques, as far as characterization and sizing are concerned, have not improved. For further improvement, in this paper we apply imaging theory developed for seismic exploration of oil and gas fields on the NDI application. Synthetic data obtained from finite difference simulations is used to illustrate the principle of imaging. Measured data is obtained with a 64-element linear array (4 MHz) on a 20-mm thick steel block with a bore hole to illustrate the imaging approach. Furthermore, three examples of real data are presented, representing a lack of fusion defect, a surface breaking crack, and porosity.     

Effects of voluntary contraction on tibial nerve somatosensory evoked potentials: gating of specific cortical responses

We evaluated vertex-parietal P37, N50, and contralateral N37 somatosensory evoked potentials (SEPs) to posterior tibial nerve stimulation during weak (20 to 30%) and strong (80 to 90%) ipsilateral gastrocnemius-soleus contraction. The results were compared with data obtained during full relaxation. P37 and N50 were attenuated significantly during weak contraction and then abolished during strong contraction, whereas the contralateral N37 was not. The N37 potential spreads over the vertex and over the ipsilateral parietal region during strong contraction. The Cz'-F3 montage was not appropriate for detecting these SEP patterns. These findings suggest that thalamic or cortical gating mechanisms affect specific cortical responses. P37 and N50 could reflect the arrival of the afferent volley into the motor areas from thalamic and cortical (subareas 1 and 2 of S1) projections. N37 could be generated in subarea 3b. Differential analysis of N37 and P37 is required in clinical practice, mainly in those conditions that involve the motor system and in those conditions in which tonic muscular activity is increased.     

Minimally invasive coronary bypass: experience at the Erasme Hospital in 1997-1998

Since the launching of cardiopulmonary bypass in 1952 the landscape of cardiac surgery has been marked by a major milestone every ten years. Though most of the cardiopathies can be surgically treated with satisfactory results in up to 90% of the cases, we must try to improve the existing results. That means--Can we do better, cheaper and less invasive? Several new surgical approaches aiming at so doing are discussed in the present report: Minimally invasive direct coronary arterial bypass (MIDCAB) which is performed through a small anterior thoracotomy; Beating heart revascularization through sternotomy; Heart Port approach; Trans Myocardial Laser Revascularization (TMLR). Those new technologies respectively offer specific advantages to the existing therapies thus represent promising alternatives in selected subcategories of patients.