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Comprehensive Method (comprehensive + method)
Selected AbstractsA new approach of selecting real input ground motions for seismic design: The most unfavourable real seismic design ground motionsEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 8 2007Chang-Hai Zhai Abstract This paper presents a new way of selecting real input ground motions for seismic design and analysis of structures based on a comprehensive method for estimating the damage potential of ground motions, which takes into consideration of various ground motion parameters and structural seismic damage criteria in terms of strength, deformation, hysteretic energy and dual damage of Park & Ang damage index. The proposed comprehensive method fully involves the effects of the intensity, frequency content and duration of ground motions and the dynamic characteristics of structures. Then, the concept of the most unfavourable real seismic design ground motion is introduced. Based on the concept, the most unfavourable real seismic design ground motions for rock, stiff soil, medium soil and soft soil site conditions are selected in terms of three typical period ranges of structures. The selected real strong motion records are suitable for seismic analysis of important structures whose failure or collapse will be avoided at a higher level of confidence during the strong earthquake, as they can cause the greatest damage to structures and thereby result in the highest damage potential from an extended real ground motion database for a given site. In addition, this paper also presents the real input design ground motions with medium damage potential, which can be used for the seismic analysis of structures located at the area with low and moderate seismicity. The most unfavourable real seismic design ground motions are verified by analysing the seismic response of structures. It is concluded that the most unfavourable real seismic design ground motion approach can select the real ground motions that can result in the highest damage potential for a given structure and site condition, and the real ground motions can be mainly used for structures whose failure or collapse will be avoided at a higher level of confidence during the strong earthquake. Copyright © 2007 John Wiley & Sons, Ltd. [source] Unstructured grid generation using LiDAR data for urban flood inundation modellingHYDROLOGICAL PROCESSES, Issue 11 2010Ryota Tsubaki Abstract Inundation disasters, caused by sudden water level rise or rapid flow, occur frequently in various parts of the world. Such catastrophes strike not only in thinly populated flood plains or farmland but also in highly populated villages or urban areas. Inundation of the populated areas causes severe damage to the economy, injury, and loss of life; therefore, a proper management scheme for the disaster has to be developed. To predict and manage such adversity, an understanding of the dynamic processes of inundation flow is necessary because risk estimation is performed based on inundation flow information. In this study, we developed a comprehensive method to conduct detailed inundation flow simulations for a populated area with quite complex topographical features using LiDAR (Light Detection and Ranging) data. Detailed geospatial information including the location and shape of each building was extracted from the LiDAR data and used for the grid generation. The developed approach can distinguish buildings from vegetation and treat them differently in the flow model. With this method, a fine unstructured grid can be generated representing the complicated urban land features precisely without exhausting labour for data preparation. The accuracy of the generated grid with different grid spacing and grid type is discussed and the optimal range of grid spacing for direct representation of urban topography is investigated. The developed method is applied to the estimation of inundation flows, which occurred in the basin of the Shin-minato River. A detailed inundation flow structure is represented by the flow model, and the flow characteristics with respect to topographic features are discussed. Copyright © 2010 John Wiley & Sons, Ltd. [source] A sociodental approach to assessing dental needs of children: concept and modelsINTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 2 2006S. GHERUNPONG Summary. Objectives., Traditional normative methods of assessing dental needs do not correspond to current concepts of ,health' and ,need'. Although there is dental research on quality of life, evidence-based practice, and oral behaviours, those concepts are rarely applied to dental needs estimation. Dental needs are usually calculated mainly from clinical data and are likely to be inaccurate. A structured comprehensive method for assessing dental needs is required. The objectives of this study are to develop and test a new sociodental system of needs assessment for overall dental needs of primary schoolchildren. Furthermore, normative and sociodental estimates of need are compared. Design., The study developed a theoretical framework and pathway algorithms of sociodental needs assessment and applied them to assessing overall dental needs. Normative dental needs were assessed using standard normative criteria. The child oral impacts on daily performances (Child-OIDP) was used to assess oral impacts, and a self-administered questionnaire was used to obtain information on demographic variables and oral behaviours. Data were analysed according to the developed algorithms. Setting., A cross-sectional survey in Suphanburi Province, Thailand. Participants., All 1126 children aged 11,12 years in a town. Main results., The sociodental approach was acceptable and not costly. In all, 54·4% had normative need under the dental needs model for life-threatening and progressive conditions, but only 16·6% had high propensity-related need; the remaining 37·8% would require dental health education or oral health promotion (DHE/OHP) or both and appropriately adjusted clinical interventions. Under the basic model of dental needs, 45·1% had normative need. Two-thirds of them (30·9%) had impact-related need and the remaining 14·2% did not have oral impacts and therefore should only receive dental health education. Only one-third of those with impact-related need had high propensity and were suitable for evidence-based conventional treatments; the remaining two-thirds should receive DHE/OHP and alternative clinical interventions. Conclusions., A sociodental system of dental needs assessment was developed and tested on school children. It decreased the estimates of conventionally assessed dental treatment needs and introduced a broader approach to care. [source] Time to establishment success for introduced signal crayfish in Sweden , a statistical evaluation when success is partially knownJOURNAL OF APPLIED ECOLOGY, Issue 5 2010Ullrika Sahlin Summary 1.,The signal crayfish Pacifastacus leniusculus is an invasive species in Sweden, threatening the red-listed nobel crayfish Astacus astacus through spreading the crayfish plague. Time-to-event models can handle censored data on such introduced populations for which the state (successful or not) is only partially known at the last observation, but even though data on introduced populations most often are censored, this type of model is usually not used for likelihood-based inference and predictions of the dynamics of establishing populations. 2.,We specified and fitted a probabilistic time-to-event model to be used to predict the time to successful establishment of signal crayfish populations introduced into Sweden. Important covariates of establishment success were found by the methods of ,model averaging' and ,hierarchical partitioning', considering model uncertainty and multi-colinearity, respectively. 3.,The hazard function that received the highest evidence based on the empirical data showed that the chances of establishment were highest in the time periods immediately following the first introduction. The model predicts establishment success to be <50% within 5 years after first introduction over the current distributional range of signal crayfish in Sweden today. 4.,Among covariates related to temperature, fish species and physical properties of the habitat, the length of the growing season was the most important and consistent covariate of establishment success. We found that establishment success of signal crayfish is expected to increase with the number of days when growth is possible, and decrease with the number of days with extremely high temperatures, which can be seen to approximate conditions of stress. 5.,Synthesis and applications. The results demonstrate lower establishment success of signal crayfish further north in Sweden, which may decrease the incentives of additional illegal introductions that may threaten the red-listed noble crayfish Astacus astacus. We provide a fully probabilistic statistical evaluation that quantifies uncertainty in the duration of the establishment stage that is useful for management decisions of invasive species. The combination of model averaging and hierarchical partitioning provides a comprehensive method to address multi-colinearity common to retrospective data on establishment success of invasive species. [source] | ||||||||||