The Experts below are selected from a list of 407766 Experts worldwide ranked by ideXlab platform
Javier Oropeza - One of the best experts on this subject based on the ideXlab platform.
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The Caracas, Venezuela, Seismic Microzoning Project: Methodology, results, and implementation for seismic risk reduction
Progress in Disaster Science, 2020Co-Authors: Michael Schmitz, Julio J. Hernández, Víctor Rocabado, Jean Domínguez, Cecilio Morales, Maxlimer Valleé, Kenny García, Javier Sánchez-rojas, André Singer, Javier OropezaAbstract:Abstract The city of Caracas has been struck by earthquakes several times in its history, and the most recent one, the M6.6 1967 event, evidenced strong site effects within the sedimentary valley. Therefore, Caracas has been the object of research related to earthquake hazard and damage since then, and a seismic microzoning Project has been formally developed in the years 2005 to 2009. The principal results constitute response spectra at different subsoil conditions within the sedimentary valley and estimation of landslide hazard for hillside areas. The Methodology used for the development of the soil response comprises probabilistic assessment of seismic hazard at rock sites; identification of soil and basin site effects; definition of microzones of similar seismic response. The seismic hazard in the area of Caracas was detailed for PGA and A1 (1-sec. period response), at four macrozones. We developed generic profiles for dynamic response using 1D equivalent linear analysis, considering variations in sediment thickness and VS,30. The analytical results were calibrated and approximate 2D-3D basin effects included. The distribution of microzones in the valley is based on geomorphologic, geological and geophysical modeling, with soil profiles from deep boreholes, and predominant periods from H/V. The earthquake triggered landslide hazard is evaluated using information regarding geology, geomorphology, geotechnical information, slope, weathering, and anthropic alterations, employing a modified Newmark method with Arias intensities. Thus, priority areas for intervention may be identified. Part of the study includes the evaluation of buildings regarding their typified structural reliability, calibrated with the 1967 Caracas earthquake damages. The derived priorities for retrofitting of existing buildings regarding their location within the different microzones are one of the key issues in the county ordinances that have been developed for the 5 counties in the Metropolitan Region. So far, one of them has been signed by the respective mayor, and the remaining 4 are in progress. Once all are signed, we expect seismic disaster risk plans to be developed to guarantee the use of the technical information for earthquake risk mitigation.
J Baker - One of the best experts on this subject based on the ideXlab platform.
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West Midlands screening histories Project: Methodology and use as an audit tool
Breast Cancer Research, 2004Co-Authors: J Hudson, Gill Lawrence, Olive Kearins, J. Walton, E O'sullivan, J BakerAbstract:The Screening Histories Project aims to assign a screening status classification to all primary breast cancers in women aged 50–64, who were diagnosed in the West Midlands from 1 March 1988 to 31 March 2001. The possible classifications are: screen detected, interval cancer, nonattender, lapsed attender and diagnosed before invite. To obtain a screening status, screen-detected cancers are downloaded from the National Breast Screening Computer System (NBSS), matched against the West Midlands Cancer Intelligence Unit's cancer registration database, and classified as screen detected. All other eligible cases from the cancer registration database are manually checked against the NBSS. This involves assigning each case a screening unit and printing individual classification forms. The screening status is dependent upon whether the woman was invited prior to diagnosis and whether she attended her invitations. The first Project phase is complete and all women diagnosed up to 31 March 1998 have been assigned a screening history. Thirty-seven per cent of women had a screen-detected cancer, 22% were interval cancers, 14% were diagnosed before invite, 11% were nonattenders and 2% were lapsed attenders. The dataset obtained by applying this algorithm is a valuable resource for the evaluation of breast screening in the West Midlands.
M. Zhao - One of the best experts on this subject based on the ideXlab platform.
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Uncertainty in the simulation of runoff due to the parameterization of frozen soil moisture using the Global Soil Wetness Project Methodology
Journal of Geophysical Research: Atmospheres, 1999Co-Authors: Andrew J. Pitman, Andrew G. Slater, C. E. Desborough, M. ZhaoAbstract:Four simulations of the region 30°N–90°N are performed using the Global Soil Wetness Project Methodology and a single land surface scheme. Four methods are used to represent soil ice: an explicit representation of the thermal and hydrological effects of soil ice; two implicit methods (which only account for the hydrological effects); and finally the simplest approach where soil ice is not accounted for. Substantial impacts on total runoff, evaporation and temperature result from the choice of parameterization. The partitioning of total runoff between drainage and surface runoff is also changed. The impacts on temperature are large enough to cause problems for “fingerprinting” of global change while the change in the runoff generation process, and the timing of maximum runoff are large enough to concern ocean modelers. Evidence presented here and elsewhere indicates that land surface schemes should include the thermal effects of soil ice melting and freezing. However, the hydrological effects of soil ice suppressing infiltration and encouraging surface runoff may be based on observations taken at a scale inappropriate to climate model parameterization. We show that for one basin, the Mackenzie, a land surface model which ignores soil ice entirely simulates runoff better than the other methodologies tested here. We therefore hypothesize that it may be preferable to not include soil ice in the runoff formulations used in land surface models until we have more observations at an appropriate spatial scale. Testing of frozen soil moisture parameterizations in other catchments with high-quality observed runoff data should be conducted to test this hypothesis.
Marianthi Theocharidou - One of the best experts on this subject based on the ideXlab platform.
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CRITIS - Human Vulnerability Mapping Facing Critical Service Disruptions for Crisis Managers
Critical Information Infrastructures Security, 2017Co-Authors: Amelie Grangeat, Julie Sina, Vittorio Rosato, Aurélia Bony, Marianthi TheocharidouAbstract:Societies rely on the exchange of essential goods and services produced by Critical Infrastructures (CI). The failure of one CI following an event could cause “cascading effects” on other CI that amplifies the crisis. Existing tools incorporate modelling and simulation techniques to analyze these effects. The CIPRNet tools go a step further by assessing the consequences on population in a static manner: people are located at their census home; their sensibility to a resource lack varies during the day. This paper improves human impacts assessment by mapping people mobility thanks to the DEMOCRITE Project Methodology. It focuses on location of people with regards to their activities and the time period (night/day, holidays), and discuss their sensibility to the lack of key infrastructure services. Human vulnerability maps of Paris area during periods of a working day time show the importance to take into account people mobility when assessing crisis impacts.
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Human Vulnerability Mapping Facing Critical Service Disruptions for Crisis Managers
2016Co-Authors: Amelie Grangeat, Julie Sina, Vittorio Rosato, Aurélia Bony-dandrieux, Marianthi TheocharidouAbstract:Societies rely on the exchange of essential goods and services produced by Critical Infrastructures (CI). The failure of one CI following an event could cause ``cascading effects'' on other CI that amplifies the crisis. Existing tools incorporate modelling and simulation techniques to analyze these effects. The CIPRNet tools go a step further by assessing the consequences on population in a static manner: people are located at their census home; their sensibility to a resource lack varies during the day. This paper improves human impacts assessment by mapping people mobility thanks to the DEMOCRITE Project Methodology. It focuses on location of people with regards to their activities and the time period (night/day, holidays), and discuss their sensibility to the lack of key infrastructure services. Human vulnerability maps of Paris area during periods of a working day time show the importance to take into account people mobility when assessing crisis impacts.
Michael Schmitz - One of the best experts on this subject based on the ideXlab platform.
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The Caracas, Venezuela, Seismic Microzoning Project: Methodology, results, and implementation for seismic risk reduction
Progress in Disaster Science, 2020Co-Authors: Michael Schmitz, Julio J. Hernández, Víctor Rocabado, Jean Domínguez, Cecilio Morales, Maxlimer Valleé, Kenny García, Javier Sánchez-rojas, André Singer, Javier OropezaAbstract:Abstract The city of Caracas has been struck by earthquakes several times in its history, and the most recent one, the M6.6 1967 event, evidenced strong site effects within the sedimentary valley. Therefore, Caracas has been the object of research related to earthquake hazard and damage since then, and a seismic microzoning Project has been formally developed in the years 2005 to 2009. The principal results constitute response spectra at different subsoil conditions within the sedimentary valley and estimation of landslide hazard for hillside areas. The Methodology used for the development of the soil response comprises probabilistic assessment of seismic hazard at rock sites; identification of soil and basin site effects; definition of microzones of similar seismic response. The seismic hazard in the area of Caracas was detailed for PGA and A1 (1-sec. period response), at four macrozones. We developed generic profiles for dynamic response using 1D equivalent linear analysis, considering variations in sediment thickness and VS,30. The analytical results were calibrated and approximate 2D-3D basin effects included. The distribution of microzones in the valley is based on geomorphologic, geological and geophysical modeling, with soil profiles from deep boreholes, and predominant periods from H/V. The earthquake triggered landslide hazard is evaluated using information regarding geology, geomorphology, geotechnical information, slope, weathering, and anthropic alterations, employing a modified Newmark method with Arias intensities. Thus, priority areas for intervention may be identified. Part of the study includes the evaluation of buildings regarding their typified structural reliability, calibrated with the 1967 Caracas earthquake damages. The derived priorities for retrofitting of existing buildings regarding their location within the different microzones are one of the key issues in the county ordinances that have been developed for the 5 counties in the Metropolitan Region. So far, one of them has been signed by the respective mayor, and the remaining 4 are in progress. Once all are signed, we expect seismic disaster risk plans to be developed to guarantee the use of the technical information for earthquake risk mitigation.
