Open Embedded Control

Embedded control devices today usually allow parameter changes, and possibly activation of different pre-implemented algorithms. Full reprogramming using the complete source code is not allowed for safety, efficiency, and proprietary reasons. For these reasons, embedded regulators are quite rigid and closed concerning the control structure. In several applications, like industrial robots, there is a need to tailor the low level control to meet specific application demands. In order to meet the efficiency and safety demands, a way of building more generic and open regulators has been developed. The key idea is to use pieces of compiled executable code as functional operators, which in the simplest case may appear as ordinary control parameters. In an object oriented framework, this means that new methods can be added to controller objects after implementation of the basic control, even at run-time. The implementation was carried out in industrially well accepted languages such as C and C++. The dynamic binding at run-time differs from ordinary dynamic linking in that only a subset of the symbols can be used. This subset is defined by the fixed part of the system. The safety demands can therefore still be fulfilled. Encouraged by results from fully implemented test cases, we believe that extensive use of this concept will admit more open, still efficient, embedded systems.     

Strong Size Effects in Supported Ionic Nanoparticles: Tailoring the Stability of NO x Storage Catalysts

Based on a well-defined model-catalyst approach, we study the particle size dependent properties of NO _x storage materials. The single-crystal based model systems are prepared on an ordered Al₂O₃ film, on which BaO nanoparticles are grown under ultrahigh-vacuum (UVH) conditions. Particle size and density are characterized by scanning tunneling microscopy (STM). The interaction with NO₂ is probed by molecular beam (MB) methods in combination with time-resolved IR reflection absorption spectroscopy (TR-IRAS). It is found that both, the stability and the formation kinetics of alumina supported barium nitrate nanoparticles show a strong dependence on particle size. Very small BaO particles are rapidly converted into nitrates, however, the resulting aggregates exhibit a strongly reduced thermal stability. Surface and bulk nitrate and nitrate features are identified by means of vibrational spectroscopy. It is concluded that the size dependencies are related to the formation and decomposition of surface-related BaNO _x species the decomposition temperature of which can be tuned over an exceptionally large temperature interval. It is suggested that the stability of these surface NO _x species is strongly modified by the underlying support.     

Assessment of cure-residual strains through the thickness of carbon–epoxy laminates using FBGs Part II: Technological specimen

This paper is a continuation of our previous study [Mulle M, Collombet F, Olivier P, Grunevald Y-H. Assessment of cure residual strains through the thickness of carbon–epoxy laminates using FBGs, part I: elementary specimen. Compos Part A 2008. doi:10.1016/j.compositesa. 2008.10.008] pertaining to the assessment of autoclave cure-induced strains through the thickness of carbon–epoxy laminates. In this first part, postulates and measurement procedures were established for cure of elementary specimens. Based on these, this study undertakes investigation on what are called technological specimens. These specimens are of the beam type and contain geometrical specificities which represent typical structural issues. In-plane process-induced strains were studied through the thickness of a thick reinforced zone using several optical fibre Bragg gratings (FBGs) sensors embedded at different levels of the ply stack. A non-uniform distribution of residual strains was detected. Once cured, the technological specimen was subjected to a heating test whose cycle was comparable to the cure cycle. Thermally induced strains were measured with the embedded FBGs. The values recorded were compared with those of cure-induced residual strains and FEM simulation. Discrepancies were observed that strongly suggest the possible influence of environmental effects and the need for the calculation to take into account the through-the-thickness variability of thermal properties.     

Near-field diagnostics of small printed antennas using theequivalent magnetic current approach

A near-field to far-field transformation based on the antenna representation by equivalent magnetic current (EMC) sources has been proposed and validated experimentally on large high-directivity antenna arrays. In this paper, the use of EMC is extended to the diagnostics of low-directivity printed antennas. The limitation of the near-field to far-field transformation applied to EMC models of low-directivity antennas, caused by the finite dimensions of the antenna ground plane, is demonstrated. A method to partially overcome this limitation by including the contribution of diffracted rays is implemented, and its effectiveness is demonstrated with antenna prototypes. It is shown that the agreement between the far-field patterns measured in an anechoic chamber and the patterns computed from the EMC model obtained from the near-field measurements is significantly improved upon, within a sector of ±90° with respect to the antenna boresight in the E plane. The influence of the near-field sampling density and topology of the EMC model on the accuracy of the predicted far-field pattern is examined     

The evolution of a successful liver transplant program in 1996: the clinical and administrative role of the anesthesiologist

The establishment of a new liver transplant program requires enormous planning and resources. Extensive negotiations must take place to ensure institutional and departmental commitments to obtain the proper equipment, personnel, and other resources. The formation of a well-trained multidisciplinary team of physicians and nurses becomes the next step. Finally, ample time must be provided to adequately deploy resources, lobby referring physicians, recruit patients, and troubleshoot problems as they arise.     

Comparison between hypo- and hyperglucidic diets on protein sparing in major visceral surgery (author's transl)

The authors compare the protein sparing effect of two diets, exclusively intravenous, including the same protein intake, but a different caloric intake, 21 calories/gm nitrogen for diet "A" (20 cases); 138 calories/gm nitrogen for diet "B" (20 cases). This has been observed during the six post-operative days of major visceral surgery: oesophagectomy, total gastrectomy, colic or rectocolic exeresis, sequestrectomy for acute pancreatitis, lots having been drawn for the diets. Daily nitrogen balances have been made and plasmatic and urinary levels of amino-acids have been measured before surgery and on the third and fifth post-operative days. Statistical exploitation is done by variance analysis (linear model of three factors) with a 99% confidence ratio: 1) Patient factor has no influence whatsoever on cumulative nitrogen balance. 2) Time factor arises only on the fourth post-operative day and only in the hypocaloric diet, leading to catabolism. 3) Metabolic condition is determinant. On no cancerous disease, superiority of hypercaloric diet is well demonstrated. On cancerous disease, nitrogen loss is only significantly different on 4th and 5th post-operative day: hypercaloric diet gives a better nitrogen balance.     

Displacement field measurements and capitalizing on experience: Application to the analysis of the rupture of holed composite plates

In this paper, we have concentrated on the use of the technique of measuring displacement fields by digital image correlation during tensile tests on different holed composite laminates. This technique is of particular use in validating the FE computation results with the aim of “capitalizing on experience”, i.e. identifying certain parameters of the material’s behavior directly from structure tests. We have demonstrated the feasibility of such an approach with the analysis of the rupture of holed composite plates (improved confidence in the failure criteria).     

Extracellular Vesicles from 50,000 Generation Clones of the Escherichia coli Long-Term Evolution Experiment

Extracellular vesicles (EVs) are critical elements of cell–cell communication. Here, we characterized the outer membrane vesicles (OMVs) released by specific clones of Escherichia coli isolated from the Long-Term Evolution Experiment after 50,000 generations (50K) of adaptation to glucose minimal medium. Compared with their ancestor, the evolved clones produce small OMVs but also larger ones which display variable amounts of both OmpA and LPS. Tracking ancestral, fluorescently labelled OMVs revealed that they fuse with both ancestral- and 50K-evolved cells, albeit in different proportions. We quantified that less than 2% of the cells from one 50K-evolved clone acquired the fluorescence delivered by OMVs from the ancestral strain but that one cell concomitantly fuses with several OMVs. Globally, our results showed that OMV production in E. coli is a phenotype that varies along bacterial evolution and question the contribution of OMVs-mediated interactions in bacterial adaptation.     

Study of complexing reactions causing the depletion of gadolinium ions from the moderator of CANDU-PHW nuclear reactors

The addition of gadolinium nitrate solution in the moderator of Hydro-Québec's Gentilly 2 reactor led to an unexpected depletion of gadolinium (Gd) by precipitation. Analysis of moderator samples revealed that bicarbonate (HCO₃^?) was the main anionic impurity. A study of the complexing reactions of Gd in concentrated solutions (0.0509M) of Gd(NO₃)₃ showed that in the absence of HCO₃^? and at pH < 6, the species in equilibrium are distributed as follows: predominant: Gd³⁺, NO₃^? and [GdNO₃]²⁺; and traces: [GdOH]²⁺ and [Gd(NO₃)₂]⁺. An increase in pH over 6.4 led to the formation of the solid phase: Gd₂(OH)_5.1(NO₃)_0.9. In the presence of bicarbonate, the solid phase Gd₂(OH)_5.0(NO₃)_1.0 is visually detected at a pH as low as 5.8. In other respects, analysis of dilute solutions (0.00065M) of Gd(NO₃)₃ containing bicarbonate allows the solid phase precipitating between pH 5.5 and 6.6 to be ascribed to the formula Gd₂(OH)₄CO₃·3H₂O. In the absence of HCO₃^?, no precipitation occurred up to pH 6.8. Finally, the loss of Gd from the moderator was established as being due to the formation of a hydroxide carbonate salt.