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961.
The ITER tokamak will be fuelled at a time averaged rate of up to 200 Pam3 s?1 requiring neutralised gas in the divertor to be pumped to balance the fuelling and remove the fusion helium and other impurities in the exhaust. This is achieved on ITER using large bespoke cryo-sorption pumps. In this paper design evolution of the ITER divertor pumping system is outlined from the 1998 configuration to the current design. Details of the new, 6 direct pump, system design which will be used in the build of ITER are given. The operating modes of the new system configuration for different plasma scenarios are described and the performance of the new system is analysed and compared with previous baselines.  相似文献   
962.
The ITER vacuum system will be one of the largest and most complex vacuum systems ever to be built. Extensive instrumentation and controls are being developed to satisfy the stringent vacuum processes necessary for the successful and safe operation of the ITER Tokamak. The complexity and deep integration of the vacuum systems within the ITER machine presents a challenge to implement all of the controls necessary for reliable operation. Several thousand valves and sensors have to be implemented within the harsh environmental conditions of the Tokamak vicinity, and require engineering of instrumentation and controls with remote electronics solutions.In this paper the status of the design of field end vacuum controls and instrumentation for the ITER vacuum systems is described. Details of the progress on selection of sensors and actuator technologies are given herein and solutions for remote device operation, including those for cryogenic devices, are described together with necessary local shielding.  相似文献   
963.
This paper addresses the problem of the robust registration of multiple observations of the same object. Such a problem typically arises whenever it becomes necessary to recover the trajectory of an evolving object observed through standard 3-D medical imaging techniques. The instances of the tracked object are assumed to be variously truncated, locally subject to morphological evolutions throughout the sequence, and imprinted with significant segmentation errors as well as significant noise perturbations. The algorithm operates through the robust and simultaneous registration of all surface instances of a given object through median consensus. This operation consists of two interwoven processes set up to work in close collaboration. The first one progressively generates a median and implicit shape computed with respect to current estimations of the registration transformations, while the other refines these transformations with respect to the current estimation of their median shape. When compared with standard robust techniques, tests reveal significant improvements, both in robustness and precision. The algorithm is based on widely-used techniques, and proves highly effective while offering great flexibility of utilization.  相似文献   
964.
A comprehensive design methodology is proposed in this paper in order to optimise E-field probes used for evaluating the specific absorption ratio within liquid equivalent tissues exposed to radiofrequency signals. Hybrid analysis approaches are investigated, combining both electromagnetic (three dimensional) and circuit simulators. This design environment can therefore be considered for enhancing E-field detectors’ performances in terms of sensitivity, isotropy, dimensions and shape. Comparisons between simulations and measurements are presented and discussed.  相似文献   
965.
Soft defect localization (SDL) is an analysis technique where changes in the pass/fail condition of a test are monitored while a laser is scanned across the device under test (DUT). This technique has proven its usefulness for quickly locating defects that are temperature, frequency, and/or voltage dependant, for example, scan logic soft fault. However, due to high sensibility at analogue circuits SDL meets great challenges. This work gives a new flow to analyze soft functional failure in advanced logic products using fault based analogue simulation and SDL. The paper will present one case study illustrating the application of analogue simulation based soft defect localization flow as an effective means to achieve fault isolation.  相似文献   
966.
The detection of dynamic photon emission by static cameras is an inexpensive approach to track circuit signal paths, but successful application depends on the signal pattern and frequency the devices are operating at. For improvement of predictability, a model has been developed, built upon the composition of operating modes and targeted to calculate the static emission signal. On single transistor test structures, the model is verified and an operating frequency correlates to the detection limit. Ring oscillator results confirm that only a fraction of the inverter switching time is accompanied by photon emission. At a real circuit it is demonstrated that operating condition limits for signal path detection in static photon emission detectors can be defined.  相似文献   
967.
The objective of this study was to understand how cosolvents influence the molecular and functional properties of globular proteins in aqueous solutions. The ultrasonic velocity, density and adiabatic compressibility of cosolvent solutions (0–50 wt% sorbitol or glycerol) were measured in the absence and presence of a globular protein (1 wt% β-lactoglobulin) at 30 °C. These measurements were used to calculate the partial specific apparent volume and adiabatic compressibility of the protein. The protein's volume decreased and its compressibility increased in the presence of high cosolvent concentrations, which were attributed to changes in the properties of the protein interior and solvation layer. Sorbitol was more effective than glycerol at decreasing the protein volume at high cosolvent concentrations, which may be because glycerol has some surface activity and may therefore accumulate around hydrophobic regions on the protein surface. Our data were used to account for the observation that sorbitol is more effective than glycerol at increasing the thermal stability and self-association of the β-lactoglobulin. A better understanding of the influence of protein–cosolvent–solvent interactions on the functionality of globular proteins may facilitate the design of protein-based products.  相似文献   
968.
This study reports the outcome of a randomized controlled trial testing a computer-tailored smoking cessation intervention based on the transtheoretical model in a general population setting in Germany. Participants of the smoking intervention study were recruited from an existing general population health examination survey in a university hospital. The sample consisted of 611 current and former smokers at baseline, and of 485 participants in the core group of baseline daily cigarette smokers. Follow-ups were conducted 6, 12, 18, and 24 months after baseline. The intervention was designed for both current and former smokers, involved up to three individualized feedback letters, and was created using expert-system technology. Based on 7-day point-prevalence abstinence and 6-month prolonged abstinence as the outcome measures, the study identified no significant differences between the intervention and control groups. Modeling the full longitudinal data in generalized estimation equation analyses, using different nonresponse procedures, and adjusting for covariates did not alter the results. We conclude that the computer-tailored transtheoretical model-based smoking cessation intervention, as delivered in this study and in this special setting, was ineffective.  相似文献   
969.
970.
REST2, a high-performance model to predict cloudless-sky broadband irradiance, illuminance and photosynthetically active radiation (PAR) from atmospheric data, is presented. Its derivation uses the same two-band scheme as in the previous CPCR2 model, but with numerous improvements. Great attention is devoted to precisely account for the effect of aerosols, in particular.Detailed research-class measurements from Billings, OK are used to assess the performance of the model for the prediction of direct, diffuse and global broadband irradiance. These measurements were made in May 2003 during a sophisticated radiative closure experiment, which involved the best radiometric instrumentation currently available and many ancillary instruments. As a whole, these exceptional measurements constitute the only known modern benchmark dataset made specifically to test the intrinsic performance of radiation models. Using this dataset as reference, it is shown that REST2 performs better than CPCR2 for irradiance, illuminance or PAR predictions. The availability of the turbidity data required by REST2 or other similar models is also discussed, as well as the effect that turbidity has on each component of broadband irradiance, PAR irradiance and illuminance, and on the diffuse/global PAR ratio.  相似文献   
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