1000 resultados para Instrument Simulation
Resumo:
Dass der Weg der parlamentarischen Mitwirkung im Bereich der Aussenpolitik steinig werden sollte, widerspiegelte sich bereits in der Entstehungsgeschichte der Aussenpolitischen Kommissionen (APK). Diese haben zum heutigen Zeitpunkt unter anderem dafür zu sorgen, dass das Parlament seine Mitwirkungsrechte in auswärtigen Angelegenheiten frühzeitig und wirk¬sam wahrnehmen kann. Nebst verschiedensten Instrumenten auf Verfassungs- und Gesetzesebene steht den APK ein wichtiges Mitwirkungsinstrument zur Verfügung: die Information und Konsultation gemäss Art. 152 Parlamentsgesetz (ParlG). Seit Inkrafttreten dieser Bestimmung im Dezember 2003 offenbart sich jedoch, dass sich die praktische Umsetzung des Gesetzesartikels mit den damaligen Vorstellungen des Gesetzgebers anlässlich der Erarbeitung dieses parlamentarischen Instrumentes nicht deckt. Der Gesetzgeber wies seiner¬zeit auf das für die Umsetzung bedeutende Vertrauensverhältnis zwischen Bundesrat und Parlament hin. Allerdings beeinflussen nun Spannungen und Konkurrenz zwischen der Exekutive und der Legislative die Umsetzung von Art. 152 ParlG. Die vorliegende Arbeit versucht, die geschichtlichen Hintergründe, die Entstehung, den Sinn und Zweck sowie die Praxis von Art. 152 ParlG vor dem Hintergrund des erwähnten Spannungsfelds und im Zusammenspiel mit den weiteren Mitwirkungsinstrumenten im Bereich der Aussenpolitik darzulegen. Comme le montre déjà l'historique des Commissions de politique extérieure (CPE), la participation du Parlement à la politique extérieure n'est pas dénuée d'obstacles. A l'heure actuelle, les CPE doivent notamment faire en sorte que le Parlement puisse faire valoir, en amont et avec efficacité, son droit de participation dans le domaine de la politique étrangère de la Suisse. Outre divers instruments figurant dans la Constitution et les lois, les CPE disposent d'un important moyen de participation: l'information et la consultation au sens de l'art. 152 de la loi sur le Parlement (LParl). Depuis l'entrée en vigueur de cette disposition en décembre 2003, il s'avère toutefois que l'application concrète de cet article de loi ne ré¬pond pas entièrement aux attentes du législateur lors de l'élaboration de cet instrument parlementaire. En effet, le législateur s'était alors basé sur la relation de confiance entre le Conseil fédéral et le Parlement, relation essentielle à la mise en oeuvre de cet article. La pratique montre cependant que la mise en oeuvre de l'art. 152 LParl est influencée par des tensions et par une relation de concurrence existant entre l'exécutif et le législatif. Le présent travail entend exposer le contexte historique de l'art. 152 LParl, son élaboration, son but et sa mise en oeuvre, tout en tenant compte des éléments de tension et des autres instruments permettant la participation en matière de politique extérieure.
Resumo:
Most sedimentary modelling programs developed in recent years focus on either terrigenous or carbonate marine sedimentation. Nevertheless, only a few programs have attempted to consider mixed terrigenous-carbonate sedimentation, and most of these are two-dimensional, which is a major restriction since geological processes take place in 3D. This paper presents the basic concepts of a new 3D mathematical forward simulation model for clastic sediments, which was developed from SIMSAFADIM, a previous 3D carbonate sedimentation model. The new extended model, SIMSAFADIM-CLASTIC, simulates processes of autochthonous marine carbonate production and accumulation, together with clastic transport and sedimentation in three dimensions of both carbonate and terrigenous sediments. Other models and modelling strategies may also provide realistic and efficient tools for prediction of stratigraphic architecture and facies distribution of sedimentary deposits. However, SIMSAFADIM-CLASTIC becomes an innovative model that attempts to simulate different sediment types using a process-based approach, therefore being a useful tool for 3D prediction of stratigraphic architecture and facies distribution in sedimentary basins. This model is applied to the neogene Vallès-Penedès half-graben (western Mediterranean, NE Spain) to show the capacity of the program when applied to a realistic geologic situation involving interactions between terrigenous clastics and carbonate sediments.
Resumo:
The critical behavior of a system constituted by molecules with a preferred symmetry axis is studied by means of a Monte Carlo simulation of a simplified two-dimensional model. The system exhibits two phase transitions, associated with the vanishing of the positional order of the center of mass of the molecules and with the orientational order of the symmetry axis. The evolution of the order parameters and the specific heat is also studied. The transition associated with the positional degrees of freedom is found to change from a second-order to a first-order behavior when the two phase transitions are close enough, due to the coupling with the orientational degrees of freedom. This fact is qualitatively compared with similar results found in pure liquid crystals and liquid-crystal mixtures.
Resumo:
An Ising-like model, with interactions ranging up to next-nearest-neighbor pairs, is used to simulate the process of interface alloying. Interactions are chosen to stabilize an intermediate "antiferromagnetic" ordered structure. The dynamics proceeds exclusively by atom-vacancy exchanges. In order to characterize the process, the time evolution of the width of the intermediate ordered region and the diffusion length is studied. Both lengths are found to follow a power-law evolution with exponents depending on the characteristic features of the model.
Resumo:
ic first-order transition line ending in a critical point. This critical point is responsible for the existence of large premartensitic fluctuations which manifest as broad peaks in the specific heat, not always associated with a true phase transition. The main conclusion is that premartensitic effects result from the interplay between the softness of the anomalous phonon driving the modulation and the magnetoelastic coupling. In particular, the premartensitic transition occurs when such coupling is strong enough to freeze the involved mode phonon. The implication of the results in relation to the available experimental data is discussed.
Resumo:
A previous study sponsored by the Smart Work Zone Deployment Initiative, “Feasibility of Visualization and Simulation Applications to Improve Work Zone Safety and Mobility,” demonstrated the feasibility of combining readily available, inexpensive software programs, such as SketchUp and Google Earth, with standard two-dimensional civil engineering design programs, such as MicroStation, to create animations of construction work zones. The animations reflect changes in work zone configurations as the project progresses, representing an opportunity to visually present complex information to drivers, construction workers, agency personnel, and the general public. The purpose of this study is to continue the work from the previous study to determine the added value and resource demands created by including more complex data, specifically traffic volume, movement, and vehicle type. This report describes the changes that were made to the simulation, including incorporating additional data and converting the simulation from a desktop application to a web application.
Resumo:
Mathematical models have great potential to support land use planning, with the goal of improving water and land quality. Before using a model, however, the model must demonstrate that it can correctly simulate the hydrological and erosive processes of a given site. The SWAT model (Soil and Water Assessment Tool) was developed in the United States to evaluate the effects of conservation agriculture on hydrological processes and water quality at the watershed scale. This model was initially proposed for use without calibration, which would eliminate the need for measured hydro-sedimentologic data. In this study, the SWAT model was evaluated in a small rural watershed (1.19 km²) located on the basalt slopes of the state of Rio Grande do Sul in southern Brazil, where farmers have been using cover crops associated with minimum tillage to control soil erosion. Values simulated by the model were compared with measured hydro-sedimentological data. Results for surface and total runoff on a daily basis were considered unsatisfactory (Nash-Sutcliffe efficiency coefficient - NSE < 0.5). However simulation results on monthly and annual scales were significantly better. With regard to the erosion process, the simulated sediment yields for all years of the study were unsatisfactory in comparison with the observed values on a daily and monthly basis (NSE values < -6), and overestimated the annual sediment yield by more than 100 %.
Resumo:
Toxicokinetic modeling is a useful tool to describe or predict the behavior of a chemical agent in the human or animal organism. A general model based on four compartments was developed in a previous study in order to quantify the effect of human variability on a wide range of biological exposure indicators. The aim of this study was to adapt this existing general toxicokinetic model to three organic solvents, which were methyl ethyl ketone, 1-methoxy-2-propanol and 1,1,1,-trichloroethane, and to take into account sex differences. We assessed in a previous human volunteer study the impact of sex on different biomarkers of exposure corresponding to the three organic solvents mentioned above. Results from that study suggested that not only physiological differences between men and women but also differences due to sex hormones levels could influence the toxicokinetics of the solvents. In fact the use of hormonal contraceptive had an effect on the urinary levels of several biomarkers, suggesting that exogenous sex hormones could influence CYP2E1 enzyme activity. These experimental data were used to calibrate the toxicokinetic models developed in this study. Our results showed that it was possible to use an existing general toxicokinetic model for other compounds. In fact, most of the simulation results showed good agreement with the experimental data obtained for the studied solvents, with a percentage of model predictions that lies within the 95% confidence interval varying from 44.4 to 90%. Results pointed out that for same exposure conditions, men and women can show important differences in urinary levels of biological indicators of exposure. Moreover, when running the models by simulating industrial working conditions, these differences could even be more pronounced. In conclusion, a general and simple toxicokinetic model, adapted for three well known organic solvents, allowed us to show that metabolic parameters can have an important impact on the urinary levels of the corresponding biomarkers. These observations give evidence of an interindividual variablity, an aspect that should have its place in the approaches for setting limits of occupational exposure.
Resumo:
Gel electrophoresis allows one to separate knotted DNA (nicked circular) of equal length according to the knot type. At low electric fields, complex knots, being more compact, drift faster than simpler knots. Recent experiments have shown that the drift velocity dependence on the knot type is inverted when changing from low to high electric fields. We present a computer simulation on a lattice of a closed, knotted, charged DNA chain drifting in an external electric field in a topologically restricted medium. Using a Monte Carlo algorithm, the dependence of the electrophoretic migration of the DNA molecules on the knot type and on the electric field intensity is investigated. The results are in qualitative and quantitative agreement with electrophoretic experiments done under conditions of low and high electric fields.
Resumo:
A screened Rutherford cross section is modified by means of a correction factor to obtain the proper transport cross section computed by partial¿wave analysis. The correction factor is tabulated for electron energies in the range 0¿100 keV and for elements in the range from Z=4 to 82. The modified screened Rutherford cross section is shown to be useful as an approximation for the simulation of plural and multiple scattering. Its performance and limitations are exemplified for electrons scattered in Al and Au.