16 research outputs found

    SEIS: Insight’s Seismic Experiment for Internal Structure of Mars

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    By the end of 2018, 42 years after the landing of the two Viking seismometers on Mars, InSight will deploy onto Mars’ surface the SEIS (Seismic Experiment for Internal Structure) instrument; a six-axes seismometer equipped with both a long-period three-axes Very Broad Band (VBB) instrument and a three-axes short-period (SP) instrument. These six sensors will cover a broad range of the seismic bandwidth, from 0.01 Hz to 50 Hz, with possible extension to longer periods. Data will be transmitted in the form of three continuous VBB components at 2 sample per second (sps), an estimation of the short period energy content from the SP at 1 sps and a continuous compound VBB/SP vertical axis at 10 sps. The continuous streams will be augmented by requested event data with sample rates from 20 to 100 sps. SEIS will improve upon the existing resolution of Viking’s Mars seismic monitoring by a factor of ∌ 2500 at 1 Hz and ∌ 200 000 at 0.1 Hz. An additional major improvement is that, contrary to Viking, the seismometers will be deployed via a robotic arm directly onto Mars’ surface and will be protected against temperature and wind by highly efficient thermal and wind shielding. Based on existing knowledge of Mars, it is reasonable to infer a moment magnitude detection threshold of Mw ∌ 3 at 40◩ epicentral distance and a potential to detect several tens of quakes and about five impacts per year. In this paper, we first describe the science goals of the experiment and the rationale used to define its requirements. We then provide a detailed description of the hardware, from the sensors to the deployment system and associated performance, including transfer functions of the seismic sensors and temperature sensors. We conclude by describing the experiment ground segment, including data processing services, outreach and education networks and provide a description of the format to be used for future data distribution

    Parmenides: an opportunity for ISO TC37 SC4?

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    Despite the many initiatives in recent years aimed at creating Language Engineering standards, it is often the case that different projects use different approaches and often define their own standards. Even within the same project it often happens that different tools will require different ways to represent their linguistic data. In a recently started EU project focusing on the integration of Information Extraction and Data Mining techniques, we aim at avoiding the problem of incompatibility among different tools by defining a Common Annotation Scheme internal to the project. However, when the project was started (Sep 2002) we were unaware of the standardization effort of ISO TC37/SC4, and so we commenced once again trying to define our own schema. Fortunately, as this work is still at an early stage (the project will last till 2005) it is still possible to redirect it in a way that it will be compatible with the standardization work of ISO. In this paper we describe the status of the work in the project and explore possible synergies with the work in ISO TC37 SC4
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