Jurnal Edukasi
Not a member yet
4879 research outputs found
Sort by
Reduced density-matrix functional theory: Correlation and spectroscopy
No full textInternational audienc
Preserving syntactic correctness while editing mathematical formulas
No full textGNU TeXmacs is a free software for editing scientific documents with mathematical formulas, which can also be used as an interface for many computer algebra systems. We present the design of a new experimental mathematical editing mode which preserves the syntactic correctness of formulas during the editing process (i.e. all formulas can be parsed using a suitable, sufficiently rich grammar). The main constraint is to remain as closely as possible to the existing presentation-oriented formula editor, which has the advantage of being very user friendly
Measurements of elliptic and triangular flow in high-multiplicity HeAu collisions at GeV
No full text630 authors, 9 pages, 4 figures, 2 tables. v2 ; Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at http://www.phenix.bnl.gov/papers.htmlInternational audienceWe present the first measurement of elliptic () and triangular () flow in high-multiplicity HeAu collisions at GeV. Two-particle correlations, where the particles have a large separation in pseudorapidity, are compared in HeAu and in collisions and indicate that collective effects dominate the second and third Fourier components for the correlations observed in the HeAu system. The collective behavior is quantified in terms of elliptic and triangular anisotropy coefficients measured with respect to their corresponding event planes. The values are comparable to those previously measured in Au collisions at the same nucleon-nucleon center-of-mass energy. Comparison with various theoretical predictions are made, including to models where the hot spots created by the impact of the three He nucleons on the Au nucleus expand hydrodynamically to generate the triangular flow. The agreement of these models with data may indicate the formation of low-viscosity quark-gluon plasma even in these small collision systems
A Generic Method for Bijections between Blossoming Trees and Planar Maps
No full textInternational audienc
The competitive impacts of global SST warming and CO<sub>2</sub> increase on Sahelian rainfall: results from CMIP5 idealized simulations
No full textInternational audiencethe West african Monsoon (WaM) is affected by large climate variability at different timescales, from interannual to multidecadal, with strong environmental and socioeconomic impacts associated to climate-related rainfall variability, especially in sahelian countries. state-of- the-art coupled climate models still show poor ability in correctly simulating the WaM historical variability and also a large spread is observed in future climate projections.in this work, climate simulations from a set of 10 CMip5 atmospheric global climate models are used to study the July-to-september WaM variability in the period 1979- 2008. the individual roles of global sst warming and CO2 concentration increase are investigated through idealized experiments simulating a 4K warmer sst and a 4x CO2 concentration, respectively.results show a dry response in sahel to 4K sst warming, with dryer conditions over western sahel. On the contrary, wet conditions are observed when CO2 is 4x increased, with the strongest response over central-eastern sahel. the precipitation changes are associated to coherent modifications in the regional atmospheric circulation: dry (wet) conditions are associated with reduced (increased) convergence in the lower troposphere, a southward (northward) shift of the african easterly Jet (aeJ), a weaker (stronger) tropical easterly Jet (teJ). the analysis of the changes in the regional and global connections of WaM dynamics reveals that in the 4K experiment the observed relationships with the global sst and the regional dynamics patterns are weaker, while in the 4xCO2 simulation the connections are more robust. Specifically, a strong coupling between WAM precipitation and Equatorial Pacific and atlantic sst is observed, along with a reinforcement of the regional connections with the saharan heat low, the aeJ and the teJ.the above results suggest a competitive action of global sst warming and CO2 increase on the WaM climate variability, with opposite effects on precipitation. the global sst warming affects sahelian precipitation by weakening the global tropical convection, while the CO2 increase results in a strengthening of the regional dynamics features associated to wet conditions in the sahel. it is argued that the large spread in CMip5 future rainfall projections may be related to the weight given to sst warming and direct CO2 effect by individual models
Measurement of diffraction dissociation cross sections in pp collisions at sqrt(s) = 7 TeV
No full textReplaced with published version. Added journal reference and DOI ; see paper for full list of authorsInternational audienceMeasurements of diffractive dissociation cross sections in pp collisions at sqrt(s) = 7 TeV are presented in kinematic regions defined by the masses M[X] and M[Y] of the two final-state hadronic systems separated by the largest rapidity gap in the event. Differential cross sections are measured as a function of xi[X]= M[X]^2/s in the region -5.5 3, log[10]M[X] > 1.1, and log[10]M[Y] > 1.1, a region dominated by DD. The cross sections integrated over these regions are found to be, respectively, 2.99 +/- 0.02 (stat) +0.32 -0.29 (syst) mb, 1.18 +/- 0.02 (stat) +/- 0.13 (syst) mb, and 0.58 +/- 0.01 (stat) +0.13 -0.11 (syst) mb, and are used to extract total SD and DD cross sections. In addition, the inclusive differential cross section, d sigma /d Delta eta[F], for events with a pseudorapidity gap adjacent to the edge of the detector, is measured over Delta eta[F] = 8.4 units of pseudorapidity. The results are compared to those of other experiments and to theoretical predictions, and found compatible with slowly-rising diffractive cross sections as a function of center-of-mass energy
Business Rule Sets as Programs: Turing-completeness and Structural Operational Semantics
No full textNational audienceProduction Rules or Business Rules are of the form 'if (condition) then (action)'. Sets of such rules can be executed on input data according to execution algorithms, or analyzed semantically using operational semantics, but the universality of systems or sets of such rules has never been characterized formally, to the best of our knowledge. Our goal is to show that for a simple execution algorithm, sets of Business Rule form a universal programming language. In other words, we show that Business Rules are Turing-complete. The proof consists in showing that a Business Rule program can be transformed in a WHILE program using additional variables. The implications of such a WHILE form include a type of structural operational semantics which may facilitate semantic analysis of Business Rule Sets
Popcorn: critical temperature, jump and sound
No full textInternational audiencePopcorn bursts open, jumps and emits a ‘pop’ sound in some hundredths of a second. The physical origin of these three observations remains unclear in the literature. We show that the critical temperature 180°C at which almost all of popcorn pops is consistent with an elementary pressure vessel scenario. We observe that popcorn jumps with a ‘leg’ of starch which is compressed on the ground. As a result, popcorn is midway between two categories of moving systems: explosive plants using fracture mechanisms and jumping animals using muscles. By synchronizing video recordings with acoustic recordings, we propose that the familiar ‘pop’ sound of the popcorn is caused by the release of water vapour
Land Use Dynamics and the Environment
No full textInternational audienceThis paper builds a benchmark framework to study optimal land use, encompassing land use activities and environmental degradation. We focus on the spatial externalities of land use as drivers of spatial patterns: land is immobile by nature, but local actions affect the whole space since pollution flows across locations resulting in both local and global damages. We prove that the decision maker problem has a solution, and characterize the corresponding social optimum trajectories by means of the Pontryagin conditions. We also show that the existence and uniqueness of time-invariant solutions are not in general guaranteed. Finally, a global dynamic algorithm is proposed in order to illustrate the spatial-dynamic richness of the model. We find that our simple set-up already reproduces a great variety of spatial patterns related to the interaction between land use activities and the environment. In particular, abatement technology turns out to play a central role as pollution stabilizer, allowing the economy to reach a time-invariant equilibrium that can be spatially heterogeneous
Stochastic representations and statistical inverse identification for uncertainty quantification in computational mechanics
No full textPlenary LectureInternational audienceThe paper deals with the statistical inverse problem for the identification of a non-Gaussian tensor-valued random field in high stochastic dimension. Such a random field can represent the parameter of a boundary value problem (BVP). The available experimental data, which correspond to observations, can be partial and limited. A general methodology and some algorithms are presented including some adapted stochastic representations for the non-Gaussian tensor-valued random fields and some ensembles of prior algebraic stochastic models for such random fields and the corresponding generators. Three illustrations are presented: (i) the stochastic modeling and the identification of track irregularities for dynamics of high-speed trains, (ii) a stochastic continuum modeling of random interphases from atomistic simulations for a polymer nanocomposite, and (iii) a multiscale experimental identification of the stochastic model of a heterogeneous random medium at mesoscale for mechanical characterization of a human cortical bone