Showing papers by "Conservatoire national des arts et métiers published in 2001"
TL;DR: In this paper, the PICACTIF SC carbon was found to be an interesting active material for supercapacitors, with a specific capacitance as high as 125 F/g.
1,125 citations
07 May 2001
TL;DR: An improvement to the design technique is proposed, which brings a gain of 3.3 dB in subchannel interference power level and an existing design technique known to be particularly relevant to the context is revisited from a frequency sampling perspective.
Abstract: The specifications of filter banks for multicarrier transmission systems with a large number of subchannels are discussed, with application to xDSL and power line communication in mind. The near perfect reconstruction (PR) modulated approach is considered and the importance, for the system, of the prototype filter delay is stressed. An existing design technique known to be particularly relevant to the context is revisited from a frequency sampling perspective. The performance results in terms of subchannel noise floor and delay are given for several filter lengths and an experimental validation is provided. Finally, an improvement to the design technique is proposed, which brings a gain of 3.3 dB in subchannel interference power level.
411 citations
TL;DR: The composition of the human cecal microbiota is poorly known because of sampling difficulties, and the numbers of strict anaerobes, bifidobacteria, Bacteroides, and members of the Clostridium coccoides group and Clostida leptum subgroup were lower in the cecum than in the feces.
Abstract: The composition of the human cecal microbiota is poorly known because of sampling difficulties. Samples of cecal fluid from eight subjects were collected via an intestinal tube. Feces were also collected. Total anaerobes, facultative anaerobes, bifidobacteria, and Bacteroides were enumerated by culture methods, and the predominant phylogenetic groups were quantified by molecular hybridization using a set of six rRNA-targeted probes. The numbers of strict anaerobes, bifidobacteria, Bacteroides, and members of the Clostridium coccoides group and Clostridium leptum subgroup were lower in the cecum. Facultative anaerobes represented 25% of total bacteria in the cecum versus 1% in the feces.
377 citations
TL;DR: In this article, the authors reviewed the research done in chemical heat pumps regarding to status of technology, current applications and their future prospect, with special reference to their utilization with solar thermal energy for cold production and upgrading/storage of heat.
262 citations
TL;DR: In this paper, an anionic membrane or a solid polymer electrolyte (SPE) was used in an alkaline fuel cell to check the possibility of using an ion-exchange capacity as well as the water content of the membrane.
259 citations
TL;DR: This paper presents JAC (Java Aspect Components), a framework for aspect-oriented programming in Java that uses the Javassist class load-time MOP and does not require any language extensions to Java.
Abstract: This paper presents JAC (Java Aspect Components), a framework for aspect-oriented programming in Java. Unlike language such as AspectJ which are mostly class-based,JAC is object-based and does not require any language extensions to Java. It uses the Javassist class load-time MOP. An aspect program in JAC is a set of aspect objects that can be dynamically deployed and undeployed on top of running application objects. Aspect objects may define three kinds of aspect methods: wrapping methods (that wrap application methods and provide the ability to run code before and after the wrapped methods), role methods (that add new functionalities to application objects), and exception handlers. The aspects composition issue is handled through a well-defined wrapping controller that specifies for each wrapped object at wrap-time, runtime or both, the execution order of aspect objects.
239 citations
TL;DR: Although there is no evidence that an anbsence of iron stores has any adverse consequences, it does indicate that iron nutrition is borderline, since any further reduction in body iron is associated with a decrease in the level of functional compounds such as haemoglobin.
Abstract: In Europe, iron deficiency is considered to be one of the main nutritional deficiency disorders affecting large fractions of the population, particularly such physiological groups as children, menstruating women and pregnant women. Some factors such as type of contraception in women, blood donation or minor pathological blood loss (haemorrhoids, gynaecological bleeding...) considerably increase the difficulty of covering iron needs. Moreover, women, especially adolescents consuming low-energy diets, vegetarians and vegans are at high risk of iron deficiency. Although there is no evidence that an absence of iron stores has any adverse consequences, it does indicate that iron nutrition is borderline, since any further reduction in body iron is associated with a decrease in the level of functional compounds such as haemoglobin. The prevalence of iron-deficient anaemia has slightly decreased in infants and menstruating women. Some positive factors may have contributed to reducing the prevalence of iron-deficiency anaemia in some groups of population: the use of iron-fortified formulas and iron-fortified cereals; the use of oral contraceptives and increased enrichment of iron in several countries; and the use of iron supplements during pregnancy in some European countries. It is possible to prevent and control iron deficiency by counseling individuals and families about sound iron nutrition during infancy and beyond, and about iron supplementation during pregnancy, by screening persons on the basis of their risk for iron deficiency, and by treating and following up persons with presumptive iron deficiency. This may help to reduce manifestations of iron deficiency and thus improve public health. Evidence linking iron status with risk of cardiovascular disease or cancer is unconvincing and does not justify changes in food fortification or medical practice, particularly because the benefits of assuring adequate iron intake during growth and development are well established. But stronger evidence is needed before rejecting the hypothesis that greater iron stores increase the incidence of CVD or cancer. At present, currently available data do not support radical changes in dietary recommendations. They include all means for increasing the content of dietary factors enhancing iron absorption or reducing the content of factors inhibiting iron absorption. Increased knowledge and increased information about factors may be important tools in the prevention of iron deficiency in Europe.
228 citations
Journal Article•
TL;DR: This work proposes a developmental approach to instruments in which they are not just understood as fabricated material objects but are also psychological and social entities that contribute to the design of information processing systems.
Abstract: The need to design information processing systems based on an anthropocentric approach, i.e., one where the design of technical objects deliberately draws from and is geared to the user’s activity, is a critical issue in the modernization of life and work environments. Within this framework, we propose a developmental approach to instruments in which they are not just understood as fabricated material objects but are also psychological and social entities. We present a model and propose ways of approaching the design of information processing systems.
198 citations
TL;DR: Polysaccharide derivatives have been extensively used as chromatographic chiral selectors in chiral stationary phases (CSPs) for the separation of enantiomers by HPLC, but they are only compatible with a limited choice of solvents, which limits their applicability.
192 citations
TL;DR: In this article, a sum up of this work is given in this paper, with many results and a discussion of mechanisms, as well as the results and mechanisms discussed in this work.
175 citations
TL;DR: The authors analyzes le mouvement et la doctrine qui se forment aujourd'hui chez les acteurs autour de l'idee de competences.
Abstract: Comment analyser le mouvement et la doctrine qui se forment aujourd’hui chez les acteurs autour de l’idee de competences ? L’auteur expose d’abord le sens de la « revolution manageriale » des competences. Il montre ensuite que cette revolution ne peut guere etre interpretee sur le mode macro-economique, en la rapportant a la crise du fordisme, mais plutot sur le mode micro-economique, comme une modification de l’echange salarial. Il souligne enfin les problemes qu’exprime, ou qu’engendre, la mise en place du management par les competences.
TL;DR: In this paper, a partitioned formulation of compressible internal fluid-structure interaction problems is presented by employing a displacement model for both the fluid and structure, which assigns two independent sets of Lagrange multipliers to the structural and fluid interfaces.
TL;DR: In this article, a new concept of hybrid supercapacitors with a conductive polymer as the positive electrode and activated carbon as the negative electrode was designed, which reached a maximum energy of 7.5 Wh/kg (total mass), and a maximum power of 250 W/kg.
Abstract: A new concept of hybrid supercapacitors has been designed with a conductive polymer as the positive electrode and activated carbon as the negative electrode. The chosen polymer was poly(4-fluorophenyl-3-thiophene) or P-4-FPT, whose good doping properties are well known Several activated carbons were tested, and the results reported here were obtained with carbons from Spectracorp (BP25 and YP17). The mass ratio of active materials was calculated to obtain the maximum cell voltage (3 V). The system studied in our laboratory was 4 cm 2 test cells which reached 48 Wh/kg of maximum energy associated with 9 kW/kg of maximum power (considering the mass of the active materials). Industrial prismatic prototypes were then assembled, containing 60 cm 2 electrodes. These prototypes reached a maximum energy of 7.5 Wh/kg (total mass), and a maximum power of 250 W/kg.
TL;DR: In this article, several variational formulations for modal analysis of bounded fluid-structure systems are investigated, taking into account in particular compressibility effects in the fluid for internal vibroacoustic problems, either gravity effects, in the context of an incompressible fluid, for hydroelastic-sloshing interaction problems.
TL;DR: In this article, the authors present the design and analysis of the piezoelectric active control of damped sandwich beams, which is done using a specific finite element, able to handle sandwich beams with a laminated surface layers and viscoelastic core.
TL;DR: Activation of 7 alpha-hydroxylation by increased close contacts of astrocytes and after glucocorticoid treatment suggested that the regulated production of 7alpha-hydroxysteroids was a key event for the neuroprotection conferred by neurosteroids.
Abstract: Robert Morfin Laboratoire de Biotechnologie Conservatoire National des Arts et M~tiers 75003, Paris, France Luboslav St6rka Institute of Endocrinology 116 94 Prague 1, Czech Republic I. Neurosteroid Metabolism in the Brain II. 7~-Hydroxylation Studies in the Brain III. 7/3-Hydroxylation Studies in the Brain 1V. 7~-Hydroxy-DHEA and 7/3-Hydroxy-DHEA as Native Anti-glucocorticoids V. The Brain and Other Organs VI. Sex Steroid Metabolism in the Brain VII. Concluding Remarks References The neurosteroids pregnenolone (PREG) and dehydroepiandrosterone (DHEA) are precursors for both oxidized and hydroxylated metabolites in the brain. Thus, brain production of 7-hydroxylated derivatives is sec- ond to that in the liver, and P4507Bl-containing hippocampus is the major site for 7c~-hydroxylation. Other P450s and/or oxido-reductive mechanisms may be responsible for 7/3-hydroxylation. In addition to regulating neuros- teroid brain levels, when produced, the 7-hydroxylated derivatives of PREG and DHEA were investigated for antiglucocorticoid-mediated neuropro- tective potencies, and both 7c~- and 7/3-hydroxy-DHEA were efficient in preventing the nuclear uptake of [3H]dexamethasone-activated glucocor- ticoid receptor in brain cells. Activation of 7c~-hydroxylation by increased close contacts of astrocytes and after glucocorticoid treatment suggested that the regulated production of 7c~-hydroxysteroids was a key event for the neuroprotection conferred by neurosteroids. ~.~2001 Academic Press.
TL;DR: A new approach is proposed based on boundary element methods (BEM), characterised by a positive equilibrium between speed and realism and great robustness, which permits one to assert that establishing deformable models with BEM is a reliable method to model objects in virtual reality environments for surgery simulation.
TL;DR: In this article, a survey of hybrid active-passive vibration control is presented, illustrated with figures and tables for helpful use by resea cational experts and used for comparison.
Abstract: A first attempt is made to survey and discuss the recent advances in hybrid active-passive struc tural vibrations control. The survey is illustrated with figures and tables for helpful use by resea...
TL;DR: In this paper, an electromechanically coupled finite element model is proposed to handle active-passive damped multilayer sandwich beams, consisting of a viscoelastic core sandwiched between layered piezoelectric faces.
Abstract: This work, in two parts, proposes, in this first part, an electromechanically coupled finite element model to handle active–passive damped multilayer sandwich beams, consisting of a viscoelastic core sandwiched between layered piezoelectric faces. The latter are modelled using the classical laminate theory, whereas the face/core/face system is modelled using classical three-layers sandwich theory, assuming Euler–Bernoulli thin faces and a Timoshenko relatively thick core. The frequency-dependence of the viscoelastic material is handled through the anelastic displacement fields (ADF) model. To make the control system feasible, a modal reduction is applied to the resulting ADF augmented system. Validation of the approach developed in this part is presented in Part 2 of the paper together with the hybrid damping performance analysis of a cantilever beam. Copyright © 2001 John Wiley & Sons, Ltd.
TL;DR: This paper presents a data model, based on linear constraints, dedicated to the representation and manipulation of multidimensional data, and restricts the orthographic dimension of an object O, defined as the dimension of the components O1, On such that O=O1×...× On.
Abstract: Most spatial information systems are limited to a fixed dimension (generally 2) which is not extensible. On the other hand, the emerging paradigm of constraint databases allows the representation of data of arbitrary dimension, together with abstract query languages. The complexity of evaluating queries though might be costly if the dimension of the objects is really arbitrary. In this paper, we present a data model, based on linear constraints, dedicated to the representation and manipulation of multidimensional data. In order to preserve a low complexity for query evaluation, we restrict the orthographic dimension of an object O, defined as the dimension of the components O_{1},\ldots,O_{n} such that O=O_{1}\times\cdots\times O_{n}. This allows to process queries independently on each component, therefore achieving a satisfying trade-off between design simplicity, expressive power of the query language and efficiency of query evaluation. We illustrate these concepts in the context of spatio-temporal databases where space and time are the natural components. This data model has been implemented in the DEDALE system and a spatio-temporal application, with orthographic dimension 2, is currently running, thus showing the practical relevance of the approach.
TL;DR: In this paper, the authors address the measures to reduce halocarbon emissions and the possibilities of adsorption technology and discuss several cases that show that ad-sorption cooling is very promising from the global warming point of view.
Abstract: As a consequence of the Kyoto Protocol and its predecessor, the Montreal Protocol, environmental considerations will play an important role in the choice of a refrigeration or heat pump system. Accordingly, sorption technology is expected to develop for cooling as well as for heat pump applications because it uses benign fluids. At the moment, liquid absorption technology is the leading technology in that field; however, adsorption offers advantages that cannot be achieved by liquid absorption technology. This article addresses the measures to reduce halocarbon emissions and the possibilities of adsorption technology. Not only are the direct emissions taken into account but also the indirect ones due to energy consumption. Several cases that show that adsorption cooling is very promising, from the global warming point of view, are considered in this article. They are: waste heat adsorption chilling, natural gas adsorption chilling, trigeneration and natural gas reversible heat pump. Adsorption air conditioning for automobiles is also discussed as a very challenging possibility for adsorption cooling.
TL;DR: In this paper, the properties of fragments and light charged particles emitted in multifragmentation of single sources formed in central 36-A MeV Gd+U collisions are reviewed.
TL;DR: The measurements show that the deepoxidation step is not influenced by Cd, and the Cd concentration used sharply inhibits the epoxidation of diatoxanthin to diadinoxanth in diatoms.
TL;DR: A model based on lineage metadata that supports the management of geographical changes in the context of a corporate cadastre application is proposed and specified and validated with the O2 object-oriented database management system.
Abstract: Nowadays one of the most successful applications of GIS is the management of a land-use cadastre. A lot of corporate GIS databases are in development, they support the legal management and distribution of cadastral maps. However, the propagation of geographical updates toward cadastral databases is still a methodological and technical problem to address in the context of large applications with many different users. This paper proposes a model based on lineage metadata that supports the management of geographical changes in the context of a corporate cadastre application. Geographical and cadastral changes are identified from an analysis of the French cadastre which acts as a case study for the development of our model. The lineage metadata model is based on the application of a direct acyclic graph that permits the management of the evolution of geographical objects and the generation of historical queries. The proposed model is specified and validated with the O_{2} object-oriented database management system.
TL;DR: This statistical approach allows identification of particular dietary patterns and dietary profiles, which might be more appropriate in studies of diet-disease associations than the single food or nutrient approach that has dominated past epidemiological research.
Abstract: Although the effects of individual foods or nutrients on the development of diseases and their risk factors have been investigated in many studies, little attention has been given to the effect of overall dietary patterns. The main objectives of this study were to identify dietary patterns and groups of subjects with similar food consumption habits, i.e. 'dietary profiles', using multiple correspondence analysis and cluster analysis. A food frequency questionnaire was sent to a large population-based sample (2923 women and 2,180 men), recruited among the 'SUpplementation en VItamines et Mineraux AntioXydants' (SU.VI.MAX.) cohort participants in France. The food items were dichotomised in order to focus the study on the highest levels of consumption. Multiple correspondence analysis allows the construction of principal components, which optimally summarise the data, and enables the construction of graphical displays. An interesting property of these graphical displays is that associations between food items can be observed on various projection planes, each category of each food item being located at the centre of gravity of the subjects corresponding to this category. An ascending hierarchical classification was unsuccessfully tried in order to determine clusters from these principal components. Therefore, a 'dissection' of the cloud of points was performed according to the orientation of the axes, providing a readily interpretable eight-dietary profiles typology for each sex. This statistical approach allows identification of particular dietary patterns and dietary profiles, which might be more appropriate in studies of diet-disease associations than the single food or nutrient approach that has dominated past epidemiological research.
TL;DR: It is concluded that conversion of DHEA to estrogens, particularly estradiol, is required to exert a mitogenic response to stimulate cell proliferation and gene expression in MCF-7 breast cancer cells.
TL;DR: Although a textbook defining the principles of career education was published in Paris as early as 1957, career education did not actually develop in Europe until a quarter of a century later as mentioned in this paper.
Abstract: Although a textbook defining the principles of career education was published in Paris as early as 1957, career education did not actually develop in Europe until a quarter of a century later. Why it eventually came into its own can be explained by a number of factors, including an ideology promoting individual success, and changes in work organisation. The ends of career education practices are seldom defined: are they aimed at making workers more flexible?; are they meant to facilitate personal achievement?Although the theoretical foundations of these educational programs are often fragile and many of them have never been rigorously evaluated, those that have appear to have reached some of their educational objectives. Several factors should determine the future of career education: the evolution of the social function of school, changes in the role attributed to work in personal development, etc.
TL;DR: In this paper, the characterization of the positive and negative doping processes of P-4-FPT was performed by cyclic voltammetry and showed high capacities, but proved no real stability in cycling experiments.
TL;DR: A linear programming method is proposed to obtain the best reduction of this problem, i.e. to compute the greatest constant c such that F is equal to c plus F′ for all feasible solutions, F′ being a quadratic pseudo-Boolean function with nonnegative coefficients.
TL;DR: In this paper, an exact three-dimensional solution of transverse shear actuation and sensing of simply-supported piezoelectric laminated plates is presented in two parts.
Abstract: This paper, in two parts, presents in this first part an exact three-dimensional solution of transverse shear actuation and sensing of simply-supported piezoelectric laminated plates. For this, the...