52 research outputs found
Portable blood gas and electrolyte analyzer evaluated in a multiinstitutional study
A recently introduced blood gas/electrolyte analyzer (SenDx 100((R)),
renamed ABL70) intended for point-of-care, near-patient, or stat
laboratory use was evaluated simultaneously in four different institutions
and compared with three different laboratory bench analyzers with respect
to imprecision, inaccuracy (assessed by tonometry), and patient-sample
analyses. The analyzer is equipped with a sensor cassette and a reagent
cartridge for 50, 100, or 200 analyses and 100 or more traditional
quality-control measurements. One analysis requires 170 microL of whole
blood and takes <90 s. Statistically, the instrument performed somewhat
better (lower CVs) for PO2 and potassium and somewhat worse for pH, PCO2,
and ionized calcium than the respective comparison analyzers. However, the
overall performance (in terms of CV and accuracy) was satisfactory in
terms of clinical (e.g., CLIA '88) goals in all institutions. The mean
difference and the CV of that difference in some 400 patient-sample
comparisons were as follows: 0.010 (+/- 0.002%) for pH, -0.65 mmHg (+/-
4%) for PCO2, -0.49 mmHg (+/- 6%) for Po2, 0.44 mmol/L (+/- 1.2%) for
sodium, -0.013 mmol/L (+/- 2.9%) for potassium, -0.016 mmol/L (+/- 2.6%)
for ionized calcium, and -0.016 L/L (+/- 7. 1%) for the hematocrit. Its
acceptable analytical performance and ease of operation make the SenDx 100
suitable for the analysis of blood gases and electrolytes
Probing quantum and classical turbulence analogy through global bifurcations in a von K\'arm\'an liquid Helium experiment
We report measurements of the dissipation in the Superfluid Helium high
REynold number von Karman flow (SHREK) experiment for different forcing
conditions, through a regime of global hysteretic bifurcation. Our
macroscopical measurements indicate no noticeable difference between the
classical fluid and the superfluid regimes, thereby providing evidence of the
same dissipative anomaly and response to asymmetry in fluid and superfluid
regime. %In the latter case, A detailed study of the variations of the
hysteretic cycle with Reynolds number supports the idea that (i) the stability
of the bifurcated states of classical turbulence in this closed flow is partly
governed by the dissipative scales and (ii) the normal and the superfluid
component at these temperatures (1.6K) are locked down to the dissipative
length scale.Comment: 5 pages, 5 figure
Using SDRT to analyze pathological conversations. Logicality, rationality and pragmatic deviances
International audienceSchizophrenia is well-known among mental illnesses for the severity of the thought dis- orders it involves, and for their widespread and spectacular manifestations ranging from deviant social behavior to delusion, not to mention affective and sensory distortions. Confronted with such a pathological con- versation, any "ordinary" speaker intuitively feels that there are some incoherencies or discontinuities. The aim of this research is to account for these using both pragmatics and formal semantics. Linguistics, especially semantics and pragmatics, is thus central to this work
Heat Load Estimator for Smoothing Pulsed Heat Loads on Supercritical Helium Loops
AbstractSuperconducting magnets for fusion are subjected to large variations of heat loads due to cycling operation of tokamaks. The cryogenic system shall operate smoothly to extract the pulsed heat loads by circulating supercritical helium into the coils and structures. However the value of the total heat loads and its temporal variation are not known before the plasma scenario starts. A real-time heat load estimator is of interest for the process control of the cryogenic system in order to anticipate the arrival of pulsed heat loads to the refrigerator and finally to optimize the operation of the cryogenic system. The large variation of the thermal loads affects the physical parameters of the supercritical helium loop (pressure, temperature, mass flow) so those signals can be used for calculating instantaneously the loads deposited into the loop. The methodology and algorithm are addressed in the article for estimating the heat load deposition before it reaches the refrigerator. The CEA patented process control has been implemented in a Programmable Logic Controller (PLC) and has been successfully validated on the HELIOS test facility at CEA Grenoble.This heat load estimator is complementary to pulsed load smoothing strategies providing an estimation of the optimized refrigeration power. It can also effectively improve the process control during the transient between different operating modes by adjusting the refrigeration power to the need. This way, the heat load estimator participates to the safe operation of the cryogenic system
SPIRAL2 Cryomodules Models: a Gateway to Process Control and Machine Learning
From simple physical systems to full production lines, numerical models could be used to minimize downtime and to optimize performances. In this article, the system of interest is the SPIRAL2 (Syst\`eme de Production d'Ions RAdioactifs en Ligne de 2e g\'en\'eration) particles accelerator cryogenic system. This paper illustrates three totally different applications based on a SPIRAL2 cryostat model: optimal controller synthesis, virtual sensor synthesis and anomaly detection. The tow firsts applications have been deployed on the system. Experimental results are used to illustrate the benefits of such applications
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