Optimization on fixed low latency implementation of GBT protocol in FPGA

In the upgrade of ATLAS experiment, the front-end electronics components are subjected to a large radiation background. Meanwhile high speed optical links are required for the data transmission between the on-detector and off-detector electronics. The GBT architecture and the Versatile Link (VL) project are designed by CERN to support the 4.8 Gbps line rate bidirectional high-speed data transmission which is called GBT link. In the ATLAS upgrade, besides the link with on-detector, the GBT link is also used between different off-detector systems. The GBTX ASIC is designed for the on-detector front-end, correspondingly for the off-detector electronics, the GBT architecture is implemented in Field Programmable Gate Arrays (FPGA). CERN launches the GBT-FPGA project to provide examples in different types of FPGA. In the ATLAS upgrade framework, the Front-End LInk eXchange (FELIX) system is used to interface the front-end electronics of several ATLAS subsystems. The GBT link is used between them, to transfer the detector data and the timing, trigger, control and monitoring information. The trigger signal distributed in the down-link from FELIX to the front-end requires a fixed and low latency. In this paper, several optimizations on the GBT-FPGA IP core are introduced, to achieve a lower fixed latency. For FELIX, a common firmware will be used to interface different front-ends with support of both GBT modes: the forward error correction mode and the wide mode. The modified GBT-FPGA core has the ability to switch between the GBT modes without FPGA reprogramming. The system clock distribution of the multi-channel FELIX firmware is also discussed in this paper

The Thin Gap Chambers database experience in test beam and preparations for ATLAS

Thin gap chambers (TGCs) are used for the muon trigger system in the forward region of the LHC experiment ATLAS. The TGCs are expected to provide a trigger signal within 25 ns of the bunch spacing. An extensive system test of the ATLAS muon spectrometer has been performed in the H8 beam line at the CERN SPS during the last few years. A relational database was used for storing the conditions of the tests as well as the configuration of the system. This database has provided the detector control system with the information needed for configuration of the front end electronics. The database is used to assist the online operation and maintenance. The same database is used to store the non event condition and configuration parameters needed later for the offline reconstruction software. A larger scale of the database has been produced to support the whole TGC system. It integrates all the production, QA tests and assembly information. A 1/12th model of the whole TGC system is currently in use for testing the performance of this database in configuring and tracking the condition of the system. A prototype of the database was first implemented during the H8 test beams. This paper describes the database structure, its interface to other systems and its operational performance.Comment: Proceedings IEEE, Nuclear Science Symposium 2005, Stockholm, Sweeden, May 200

Design and implementation of the web : linguistic and ethnographic atlas of Colombia

The Atlas Lingüístico y Etnográfico de Colombia (Linguistic and Ethnographic Atlas of Colombia), known by “ALEC” is a compilation of popular speaking Spanish of the populations of Colombia; such research was carried out for more than fifty years. The result of this work is a collection of thematic maps organized in six volumes and its supplements in analog format. In that sense was created the project entitles “Interactive ALEC” which main objective is to develop a digital and interactive web version of the ethnographic and Linguistic Atlas of Colombia (1983) and its supplements. In this way the Corpus linguistics research group belonging to the Institute Caro y Cuervo and the research group NIDE of the Universidad Distrital “Francisco José de Caldas” have been working together in the design and development of the Atlas Web, that allows the visualization and consulting of the spatial information contained in the volume III of the analog ALEC Atlas, applying concepts of Geographical Information Systems and web cartography. Therefore, the objective of this paper is to show the process of design and development of the web prototype of the ALEC as a collection of static and dynamic maps, which show spatial information, combined with multimedia content, taking into account that in addition to all maps, the total compendium includes images, illustrations, photographs, audio and text comments. Likewise, the interactive ALEC is a good example of how to use geo-technology tools nowadays, because they are essential for the dissemination of geo linguistic information through internet, achieving more access and distribution of the Atlas web

Oceanographic Weather Maps: Using Oceanographic Models to Improve Seabed Mapping Planning and Acquisition

In a world of high precision sensors, one of the few remaining challenges in multibeam echosounding is that of refraction based uncertainty. A poor understanding of oceanographic variability can lead to inadequate sampling of the water mass and the uncertainties that result from this can dominate the uncertainty budget of even state-of-the-art echosounding systems. Though dramatic improvements have been made in sensor accuracies over the past few decades, survey accuracy and efficiency is still potentially limited by a poor understanding of the “underwater weather”. Advances in the sophistication of numerical oceanographic forecast modeling, combined with ever increasing computing power, allow for the timely operation and dissemination of oceanographic nowcast and forecast model systems on regional and global scales. These sources of information, when examined using sound speed uncertainty analysis techniques, have the potential to change the way hydrographers work by increasing our understanding of what to expect from the ocean and when to expect it. Sound speed analyses derived from ocean modeling system’s three-dimensional predictions could provide guidance for hydrographers during survey planning, acquisition and post-processing of hydrographic data. In this work, we examine techniques for processing and visualizing of predictions from global and regional operational oceanographic forecast models and climatological analyses from an ocean atlas to better understand how these data could best be put to use to in the field of hydrograph

Atlas of Hydrologic Characteristics of the Wolf River Basin

An atlas of the hydrologic characteristics of the WolfRiver basin in West Tennessee is derived by using a Geographic Information System (GIS) to simulate the watershed\u27s hydrologic response. A 30-meter digital elevation model (DEM), extracted from the National Elevation Dataset (NED) and managed by United States Geologic Survey (USGS), is used to develop the database of watershed characteristics. Arc Hydro, created by Environmental Systems Research Institute (ESRI), and the Geospatial Hydrologic Modeling System (HEC-GeoHMS) program, created by the United States Army Corps of Engineers’ Hydrologic Engineering Center (USACE-HEC), are used to delineate the watershed of the Wolf River basin and develop the hydrologic characteristics (physical parameters) of the main streams (creeks), such as length, slope, subbasin area, longest flow path, basin slope, centroid elevation, and centroidal flow path. These topographic characteristics were needed to analyze and evaluate every subbasin of the WolfRiver floodplain from its outlet to its headwaters. The development of an atlas that contains such information would be an invaluable source of information to municipalities and consultants in the design of storm water networks, the design of box culverts, the design of sanitary sewer systems and interceptors, the complete analysis of flood plains, and the development of a flood hydrograph for each subdivision