Search results for "Spur"

Pollution patterns in the upper troposphere over Europe and Asia observed by CARIBIC

2014

Abstract Between May 2005 and March 2008 the CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container) observatory was deployed to make atmospheric observations on 42 flights between Frankfurt, Germany and Manila, the Philippines. This nearly 3 year flight series provides information about atmospheric composition in the upper troposphere over Europe and Asia during all seasons and was used to investigate seasonal and regional differences in trace gas distributions and the influence of long range transport and local convection on composition. The flight route was separated into three different regions having characteristic differences in transp…

The analysis of poverty in Italy. A fuzzy dynamic approach

2004

The commonly used criterion to sharply separate the poor from the non poor on the basis of a poverty threshold appears to be too severe in comparison with the nature of poverty. The latter is multidimensional in its components (domain) and continue in its states (codomain). Moreover an income-based poverty line allows for a remarkable number of spurious transitions below and over that line, which do not correspond to true variations in household’s standard of living. This study starts from the analysis of common (with crisp states) transition matrices; then a fuzzy multidimensional poverty indicator is built. In conclusion, fuzzy states transition matrices synthesize interpretative content …

On estimating contemporaneous quarterly regional GDP

2007

Subnational regional jurisdictions rarely have at their disposal a reasonable array of timely statistics to monitor their economic condition. In light of this, we develop a procedure that simultaneously estimates a quarterly time series for all regions of a country based upon quarterly national and annual regional data. While other such techniques exist, we suggest a temporal error structure that eliminates possible spurious jumps. Using our approach, regional analysts should now be able to distribute national growth among regions as soon as quarterly national figures are released. In a Spanish application, we detail some practicalities of the process and show that our proposal produces bet…

Quatro temas kelsenianos

2011

Causal Inference in Geoscience and Remote Sensing From Observational Data

2020

Establishing causal relations between random variables from observational data is perhaps the most important challenge in today’s science. In remote sensing and geosciences, this is of special relevance to better understand the earth’s system and the complex interactions between the governing processes. In this paper, we focus on an observational causal inference, and thus, we try to estimate the correct direction of causation using a finite set of empirical data. In addition, we focus on the more complex bivariate scenario that requires strong assumptions and no conditional independence tests can be used. In particular, we explore the framework of (nondeterministic) additive noise models, …

Modeling lightning observations from space-based platforms (CloudScat.jl 1.0)

2020

This is an open access article. This work is distributed under the Creative Commons Attribution 4.0 License.

Digital background calibration algorithm and its FPGA implementation for timing mismatch correction of time-interleaved ADC

2019

Sample time error can degrade the performance of time-interleaved analog to digital converters (TIADCs). A fully digital background algorithm is presented in this paper to estimate and correct the timing mismatch errors between four interleaved channels, together with its hardware implementation. The proposed algorithm provides low computation burden and high performance. It is based on the simplified representation of the coefficients of the Lagrange interpolator. Simulation results show that it can suppress error tones in all of the Nyquist band. Results show that, for a four-channel TIADC with 10-bit resolution, the proposed algorithm improves the signal to noise and distortion ratio (SN…

TheINTEGRALspectrometer SPI: performance of point-source data analysis

2005

The performance of the SPI point-source data analysis system is assessed using a combination of simulations and of observations gathered during the first year of INTEGRAL operations. External error estimates are derived by comparing source positions and fluxes obtained from independent analyses. When the source detection significance provided by the SPIROS imaging reconstruction program increases from ∼10 to ∼100, the errors decrease as the inverse of the detection significance, with values from ∼10 to ∼1 arcmin in positions, and from ∼10 to ∼1 per cent in relative flux. These errors are dominated by Poisson counting noise. Our error estimates are consistent with those provided by the SPIRO…

Suitability of the VOF Approach to Model an Electrogenerated Bubble with Marangoni Micro-Convection Flow

2022

When a hydrogen or oxygen bubble is created on the surface of an electrode, a micro-convective vortex flow due to the Marangoni effect is generated at the bottom of the bubble in contact with the electrode. In order to study such a phenomenon numerically, it is necessary to be able to simulate the surface tension variations along with a liquid-gas interface, to integrate the mass transfer across the interface from the dissolved species present in the electrolyte to the gas phase, and to take into account the moving contact line. Eulerian methods seem to have the potential to solve this modeling. However, the use of the continuous surface force (CSF) model in the volume of fluid (VOF) framew…

Der Spur auf der Spur. Sur les traces de la trace

2016

Hinter dem scheinbar einfachen lexikalischen Gewand der »Spur« verbirgt sich eine überraschende Komplexität: Was ist eigentlich eine Spur? Was sind ihre typischen Merkmale? Wodurch unterscheidet sie sich von Abdruck, Zeichen und Indiz? Die Beiträge des vorliegenden Bandes reflektieren den Spurbegriff aus deutsch-französischer sowie aus interdisziplinärer Perspektive. Zu Wort kommen Philosophie, Literatur, Geschichte, Archäologie, Kunstgeschichte, Urbanistik, Kulturwissenschaft und Psychoanalyse.