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The computation of time series for hard-rock site conditions, either as input motion for site response calculations or for applications to installations constructed on this site type, is a crucial step for seismic hazard assessment. The current state-of-the-art is to apply physics-based corrections to surface motions to eliminate the influence of site effects for retrieving the underlying bedrock motion. Here we evaluate the application of the generalized inversion method (GIT) for deconvolving surface recordings to obtain hard-rock time series at the amplification-free seismic bedrock. The method includes an event-specific phase scaling approach on the surface recordings that takes changes in the signal duration between the surface and the seismic bedrock into account.We choose a total of 90 KiK-net surface-downhole sites for validation which do not have a significant velocity contrast below the downhole sensors and with the latter being located at sufficient depth so that they are not significantly impaired by downgoing waves. By comparing the empirical predictions from surface recordings with time series that have been recorded at the downhole sensors, we assess the accuracy of the predictions. In contrast to empirical and one-dimensional modelling approaches, which significantly overestimate the level of hard-rock ground motion for frequencies greater than a few Hz, we find quite high correlations and small variations in both spectral shape and amplitude over the entire frequency range. This approach delivers a data set that facilitates the development of reference ground-motion models., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

The Multi-Parameter Wireless Sensing (MPwise) system is an innovative instrumental design that allows different sensor types to be combined with relatively high-performance computing and communications components. These units, which incorporate off-the-shelf components, can undertake complex information integration and processing tasks at the individual unit or node level (when used in a network), allowing the establishment of networks that are linked by advanced, robust and rapid communications routing and network topologies. The system (and its predecessors) was originally designed for earthquake risk mitigation, including earthquake early warning (EEW), rapid response actions, structural health monitoring, and site-effect characterization. For EEW, MPwise units are capable of on-site, decentralized, independent analysis of the recorded ground motion and based on this, may issue an appropriate warning, either by the unit itself or transmitted throughout a network by dedicated alarming procedures. The multi-sensor capabilities of the system allow it to be instrumented with standard strong- and weak-motion sensors, broadband sensors, MEMS (namely accelerometers), cameras, temperature and humidity sensors, and GNSS receivers. In this work, the MPwise hardware, software and communications schema are described, as well as an overview of its possible applications. While focusing on earthquake risk mitigation actions, the aim in the future is to expand its capabilities towards a more multi-hazard and risk mitigation role. Overall, MPwise offers considerable flexibility and has great potential in contributing to natural hazard risk mitigation.

Simulations of strong ground motion within the Santiago de Chile Metropolitan area were carried out by means of 3-D deterministic wave propagation tool based on the spectral element method. The simulated events take into account the pronounced interface between the low-velocity sedimentary basin and the bedrock as well as topography of the area. To verify our model we simulated a regional earthquake recorded by a dense network installed in the city of Santiago for recording aftershock activity after the 2010 February 27 Maule main shock. The results proof the alluvial basin amplification effects and show a strong dependence of spectral amplification in the basin on the local site conditions. Moreover, we studied the seismic response due to a hypothetical M(w) = 6.0 event occurring along the active San Ramon Fault, which is crossing the eastern edge of the city. The scenario earthquakes exhibit that an unfavourable interaction between fault rupture, radiation mechanism and complex geological and topographic conditions in the near-field region may give rise to large values of peak ground velocity in the basin. Finally, 3-D numerical predictions of ground motion are compared with the one computed according to ground motion prediction equations selected among the next generation attenuation relationships, in terms of ground motion peak values and spectral acceleration. The comparison underlines that the 3-D scenario simulations predict a significantly higher level of ground motion in the Santiago basin, especially over deep alluvial deposits. Moreover, also the location of the rupture nucleation largely influences the observed shaking pattern.

System Erde; 1, Central Asia was identified as one of the regions of the world with the highest seismic hazard and risk. However, the actual lack and heterogeneity of available seismological and vulnerability data make any possible seismic risk scenario highly uncertain. In order to improve seismic risk assessment in Central Asia efforts must be carried out to both increase the seismological knowledge in the area and to update and harmonise the existing vulnerability data set in the different countries. To this regard, within the Central Asia Cross-Border Natural Disaster Prevention (CASCADE) project, financed by the German Federal Foreign Office, a cross-border seismological and strong motion network in Central Asia (CAREMON) was installed. Microzonation studies in the capitals of Kyrgyzstan and Uzbekistan were started, and those for Kazakhstan, Tajikistan and Turkmenistan were triggered. The collection of a harmonised (in terms of the European Macroseismic Scale EMS) building vulnerability data base was also achieved, and a capacity building and training program accompanied all the different tasks of the project. All these activities were carried out within the framework of, and supported by, the Global Change Observatory Central Asia (GCO-CA). The digital data collected by the CAREMON network will allow to improve localisation of the seismicity in the area and to improve completeness of earthquake catalogues necessary for sounded seismic hazard assessment at regional scale. The results of the microzonation will be exploited for improving the seismic hazard and risk assessment in the capitals. Attempts were already carried out for Bishkek. Follow-up activities, including the establishment of a vertical array of accelerometer in Bishkek, are foreseen for further improving seismic hazard and risk analysis in Central Asia.

The RF part of the new high current injector-linac HSI consists of five cavities with the new operating frequency of 36 MHz instead of 27 MHz of the removed Wideroe type injector. The calculated power requirements of the cavities including beam load in three structures were between 110 kW for a rebuncher and 1.75 MW pulse-power for the two IH-cavities. The beam load is up to 150 kW for the RFQ and up to 750 kW for the two drift tube tanks. An additional 36 MHz debuncher in the transfer line to the Synchrotron (SIS) will need 120 kW pulse power. We decided to fulfil these demands with amplifiers of only two power classes, namely three amplifiers with 2 MW and six amplifiers with 200 kW pulse output power. The latter ones are also used as drivers for the 2 MW stages. The 200 kW amplifiers were specified in detail by GSI and ordered in the industry. The three 2 MW final amplifiers were designed, constructed and built by GSI. The paper gives an overview of the complete RF system and the operating performance of amplitude and phase control with beam load. It further describes some specialities of the new 2 MW amplifiers like the simplicity of the anode circuit, a very sophisticated socket for a cathode driven amplifier with cathode on dc ground, the parasitic mode-suppression, shielding and filtering of unallowable RF-radiation and operating experience since October 1999., Comment: Linac Contribution Poster THE05

This paper focuses on the constitution of vocational knowledge, and the development of an analytical framework that seeks to identify and characterise how that knowledge is constituted. Bernstein’s concept of a ‘region’ is outlined as a socio-epistemic entity into which various aspects of disciplinary knowledge are ‘recontextualised’ to meet the requirements of practice. This leads to a discussion of both the ‘internal’ social relations that exist between organisations involved in recontextualisation, and the ‘external’ factors that influence the character of regions, including relations between occupations and the broader macro-context pertinent to vocational practice. Issues of ‘recontextualisation capability’ are considered particularly important for understanding the nature of regions. While it is possible to conceive this capability at a variety of ‘levels’ or in relation to various activities, how knowledge achieves validity in the vocational community and provides a basis for a curriculum is particularly foregrounded here. The discussion is bolstered with examples of regions and recontextualisation processes taken from recent studies of higher apprenticeships in England between 2012 and 2014. In addition, there is some brief engagement with comparative research into vocational education and training systems in order to better understand how differing national contexts and policy-driven change may (re)orientate regions and their capacity to recontextualise.

In this work, the development of an on-site early warning system for Bishkek (Kyrgyzstan) is outlined. Several low cost sensors equipped with MEMS accelerometers are installed in eight buildings distributed within the urban area. The different sensing units communicate each other via wireless links and the seismic data are streamed in real-time to the data center using internet. Since each single sensing unit has computing capabilities, software for data processing can be installed to perform decentralized actions. In particular, each sensing unit can perform event detection task and run software for on-site early warning. If a description for the vulnerability of the building is uploaded in the sensing unit, this piece of information can be exploited to introduce the expected probability of damage in the early-warning protocol customized for a specific structure.