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Conventional Data (conventional + data)
Selected AbstractsSeismic evaluation of 1940s asymmetric wood-frame building using conventional measurements and high-definition laser scanningEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 10 2009Khalid M. Mosalam Abstract This study presents results from shake table experiments of a wood-frame building conducted at the University of California, Berkeley. A 13.5-ft × 19.5-ft two-story wood-frame building representing San Francisco 1940s design of a residential building with a garage space on the first story (house-over-garage) was tested. The test building was subjected to scaled ground motion based on Los Gatos record from Loma Prieta 1989 earthquake. The strong motion time history was scaled to match design spectra of a site in Richmond district of San Francisco. The test results demonstrated the seismic vulnerability of the test building due to soft story mechanism and significant twisting when shaken in two horizontal directions. In addition to conventional instrumentation for measuring acceleration and position of selected points of the test building, high-definition laser scanning technology was employed to assess global and local anomalies of the building after the shake table tests. The analysis conducted in this study showed very good correlation between conventional data recorded from position transducers and the laser scans. These laser scans expanded limits of conventional data at discrete points and allowed analyzing the whole building after shaking. Copyright © 2009 John Wiley & Sons, Ltd. [source] High-resolution seismic imaging in deep sea from a joint deep-towed/OBH reflection experiment: application to a Mass Transport Complex offshore NigeriaGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 3 2010S. Ker SUMMARY We assess the feasibility of high-resolution seismic depth imaging in deep water based on a new geophysical approach involving the joint use of a deep-towed seismic device (SYSIF) and ocean bottom hydrophones (OBHs). Source signature measurement enables signature deconvolution to be used to improve the vertical resolution and signal-to-noise ratio. The source signature was also used to precisely determine direct traveltimes that were inverted to relocate source and receiver positions. The very high accuracy of the positioning that was obtained enabled depth imaging and a stack of the OBH data to be performed. The determination of the P -wave velocity distribution was realized by the adaptation of an iterative focusing approach to the specific acquisition geometry. This innovative experiment combined with advanced processing succeeded in reaching lateral and vertical resolution (2.5 and 1 m) in accordance with the objectives of imaging fine scale structures and correlation with in situ measurements. To illustrate the technological and processing advances of the approach, we present a first application performed during the ERIG3D cruise offshore Nigeria with the seismic data acquired over NG1, a buried Mass Transport Complex (MTC) interpreted as a debris flow by conventional data. Evidence for a slide nature of a part of the MTC was provided by the high resolution of the OBH depth images. Rigid behaviour may be inferred from movement of coherent material inside the MTC and thrust structures at the base of the MTC. Furthermore, a silt layer that was disrupted during emplacement but has maintained its stratigraphic position supports a short transport distance. [source] Intra-Household Resource Allocation, Consumer Preferences and Commodity Tax Reforms: Australian EvidenceTHE ECONOMIC RECORD, Issue 247 2003Paul Blacklow Empirical analysis of household expenditure behaviour has traditionally ignored the issue of resource allocation between household members, assuming that they have identical or unitary preferences. This paper relaxes that assumption, develops a household sharing rule and proposes intra-household demand systems that are able to identify differences in the preferences of members from conventional data. The resulting price and expenditure elasticities are used to demonstrate that collective demand models suggest different directions for commodity tax reforms to those implied by the traditional unitary model. [source] Impact study of the 2003 North Atlantic THORPEX Regional CampaignTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 615 2006Nadia Fourrié Abstract An experiment took place during autumn 2003 with the aim of testing the feasibility of an operational targeting of observations over the North Atlantic Ocean in the context of the international programme THORPEX. The purpose of this paper is to evaluate the impact of these additional observations in the French operational model ARPEGE during the last three weeks of the campaign. Results are shown for large regions over and around the North Atlantic Ocean and for specific verification areas. Over Europe, the addition of observations is slightly beneficial for the forecast, mostly in the low troposphere over wide areas and above 100 hPa. However, the impact of extra data is more significant but also more mixed for the dedicated verification areas: they are case, forecast-range and level dependent. In addition, the information content is studied with the Degrees of Freedom for Signal (DFS) for the evaluation of the observation impact on the analysis of one case of December 2003. Firstly, the variations of the DFS have been illustrated in a simplified data assimilation system. It has been found for that case that satellite data have the most important global contribution to the overall analysis, especially the humidity sensitive infrared radiances. For the conventional data, the wind measurements of the aircraft and from the geostationary satellites are the most informative. For the targeted area, the data from aircraft and the dropsondes have the largest DFS. It has been noted that the DFS of the dropsondes located in the sensitivity maximum is larger than the other one even if there is no link between the DFS and the forecast. However, the impact of the dropsondes grows with respect to the forecast range and leads to an improvement of the forecast for this case. Copyright © 2006 Royal Meteorological Society [source] Validation of precipitable water from ECMWF model analyses with GPS and radiosonde data during the MAP SOPTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 612 2005Olivier Bock Abstract Precipitable water vapour contents (PWCs) from European Centre for Medium-Range Weather Forecasts (ECMWF) analyses have been compared with observations from 21 ground-based Global Positioning System receiving stations (GPS) and 14 radiosonde stations (RS), covering central Europe, for the period of the Mesoscale Alpine Programme experiment special observing period (MAP SOP). Two model analyses are considered: one using only conventional data, serving as a control assimilation experiment, and one including additionally most of the non-operational MAP data. Overall, a dry bias of about ,1 kg m,2 (,5.5% of total PWC), with a standard deviation of ,2.6 kg m,2 (13% of total PWC), is diagnosed in both model analyses with respect to GPS. The bias at individual sites is quite variable: from ,4 to ,0 kg m,2. The largest differences are observed at stations located in mountainous areas and/or near the sea, which reveal differences in representativeness. Differences between the two model analyses, and between these analyses and GPS, are investigated in terms of usage and quality of RS data. Biases in RS data are found from comparisons with both model and GPS PWCs. They are confirmed from analysis feedback statistics available at ECMWF. An overall dry bias in RS PWC of 4.5% is found, compared to GPS. The detection of RS biases from comparisons both with the model and GPS indicates that data screening during assimilation was generally effective. However, some RS bias went into the model analyses. Inspection of the time evolution of PWC from the model analyses and GPS occasionally showed differences of up to 5,10 kg m,2. These were associated with severe weather events, with variations in the amount of RS data being assimilated, and with time lags in the PWCs from the two model analyses. Such large differences contribute strongly to the overall observed standard deviations. Good confidence in GPS PWC estimates is gained through this work, even during periods of heavy rain. These results support the future assimilation of GPS data, both for operational weather prediction and for mesoscale simulation studies. Copyright © 2005 Royal Meteorological Society. [source] | ||||||||||