21 research outputs found
Web-based technology for storage and processing of multi-component data in seismology
Seismic databases and processing tools currently available are mainly limited to classic three-component seismic recordings and cannot handle collocated multi-component, multi-disciplinary datasets easily. Further, these seismological databases depend on event-related data and are not able to manage state of the art continuous waveform data input as well. None of them allows for automated request of data available at seismic data centers or to share specific data to users outside one institute. Some seismic databases even depend on licensed database engines, which contradicts the open source character of most software packages used in seismology.
This study intends to provide a suitable answer to the deficiencies of existing seismic databases. SeisHub is a novel web-based database approach created for archiving, processing, and sharing geophysical data and meta data (data describing data), particularly adapted for seismic data. The implemented database prototype offers the full functionality of a native XML database combined with the versatility of a RESTful Web service. The XML database itself uses a standard relational database as back-end, which is currently tested with PostgreSQL (http://www.postgres.org) and SQLite (http://www.sqlite.org). This sophisticated structure allows for the usage of both worlds: on the one hand the power of the SQL for querying and manipulating data, and one the other hand the freedom to use any standard connected to XML, e.g. document conversion via XSLT (Extensible Stylesheet Language Transformations) or resource validation via XSD (XML Schema). The actual resources and any additional services are available via fixed Uniform Resource Identifiers (URIs), where as the database back-end stores the original XML documents and all related indexed values. Indexes are generated using the XPath language and may be added at any time during runtime. This flexibility of the XML/SQL mixture introduced above enables the user to include parameters or results as well as meta data from additional or yet unknown monitoring techniques at any time. SeisHub also comprises features of a “classical seismic database” providing direct access to continuous seismic waveform data and associated meta data. Additionally, SeisHub offers various access protocols (HTTP/HTTPS, SFTP, SSH), an extensible plug-in system, user management, and a sophisticated web-based administration front-end. The SeisHub database is an open source project and the latest development release can be downloaded via the project home page http://www.seishub.org.
The SeisHub database has already been deployed as central database component within two scientific projects: Exupéry (http://www.exupery-vfrs.de), a mobile Volcano Fast Response System (VFRS), and BayernNetz, the seismological network of the Bavarian Seismological Service (Erdbebendienst Bayern; http://www.erdbeben-in-bayern.de)
Modulation of glycinergic neurotransmission may contribute to the analgesic effects of propacetamol
ObsPy – What can it do for data centers and observatories?
Data acquisition by seismic centers relies on real-time systems, like SeisComP3, Antelope and Earthworm. However, these are complex systems that are designed for fast and precisely defined standard real-time analyses. Therefore, it is not a simple task to access or modify internal routines, and to integrate them into custom-processing workflows or to perform in-depth data analyses. Often a library is necessary that provides convenient access to data and allows easy control over all of the operations that are to be performed on the data. ObsPy is such a library, which is designed to access and process seismological waveform data and metadata. We use short and simple examples here to demonstrate how effective it is to use Python for seismological data analysis. Then, we illustrate the general capabilities of ObsPy, and highlight some of its specific aspects that are relevant for seismological data centers and observatories, through presentation of real-world examples. Finally, we demonstrate how the ObsPy library can be used to develop custom graphical user interface applications.<br />
ObsPy : a bridge for seismology into the scientific Python ecosystem
info:eu-repo/semantics/publishe
Investigation into the Equilibrium of Iridium Catalysts for the Hydroformylation of Olefins by Combining In Situ High-Pressure FTIR and NMR Spectroscopy
A detailed quantitative study of
phosphine-modified hydrido iridium
complexes relevant for the hydroformylation reaction has been performed
using HP-FTIR and HP-NMR spectroscopy. The equilibrium composition
under typical reaction conditions has been characterized. Investigation
of the temperature dependency allowed even for a distinction between
both configurational isomers of [HIr(CO)<sub>2</sub>(PPh<sub>3</sub>)<sub>2</sub>]. The trihydride complex [H<sub>3</sub>Ir(CO)(PPh<sub>3</sub>)<sub>2</sub>] is part of the investigated equilibrium depending
on the ratio of <i>p</i>(H<sub>2</sub>)/<i>p</i>(CO). Single rate constants for the sequence of corresponding equilibrium
reactions have been estimated from stopped-flow experiments and conventional
measurements, monitoring the concentrations after changing reactant
concentrations