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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Anticipation in skilled performance

Rowe, Richard M. January 1997 (has links)
No description available.
52

Investigation of a biochemical marker of pulmonary eosinophil influx as a predictive assay for low molecular weight respiratory sensitisers

Blackwell, Malcolm Peter January 1999 (has links)
No description available.
53

Hazard, risk and waste management : the constant struggle for public tolerability

Gerrard, Simon January 1995 (has links)
No description available.
54

An information-theoretical approach to identify seismic precursors and earthquake-causing variables

Lopes da Silva Valencio, Arthur January 2018 (has links)
Several seismic precursors and earthquake-causing variables have been proposed in the last decades based on physical considerations and case observations, however none has been confirmed on long datasets using linear analysis. This work adopts an information-theoretical approach to investigate the occurrence of causal flow between these precursors and causing variables and seismicity. It starts by introducing the key concepts in seismology and presenting the current main precursor candidates. Four variables will be considered as possible precursors or anomalies leading to earthquakes: large tidal amplitudes, temporal fluctuations in the Gutenberg-Richter's b-value, surface gravity changes, and preceding anomalous seismicity patterns. To perform the causality test between these variables and their effects, it is developed a method which allows the fast calculation of Transfer Entropy for any two time-series, detecting the direction of the flow of information between the variables of interest. The method is tested to coupled logistic maps and networks with different topologies before application to geophysical events. The analysis shows mutual information relating to coupling strength and also allows inference of the causal direction from data using the Transfer Entropy, both in bivariate systems and in networks. The method was then applied to the earthquake analysis for an interval of 4018 days on an area comprising the Japan trench. Within a conservative margin of confidence, the results could not at this point confirm any of the four precursor options considered, but future work can clarify initial suggestions regarding tidal amplitudes link to seismicity, and pre-seismic gravity changes and cumulative daily magnitude anomalies. The Matlab/Octavecodes for our method are open-source and available at https://github.com/artvalencio/causality-toolbox We hope the method is able to support the quest for other precursor candidates, and to assist other fields of knowledge.
55

Son preference and fertility in China, South Korea, and the United States

Min, Ho Sik 15 May 2009 (has links)
The goal of this dissertation is to contribute in three ways to the literature on son preference and fertility through a comparative perspective. First, I examine the impact of son preference on fertility in China and South Korea compared with the United States. The impact that a female birth has on the likelihood of a woman having another birth is of the most concern: Women who have one or two daughter(s) as previous child(ren) are expected to be more likely to experience the hazard of having a second or a third birth. Second, my dissertation attempts to examine the effects of women’s status on son preference if women’s education reduces son preference. Third, my dissertation examines son preference and fertility in the U.S. Even though the U.S. has never shown son preference regarding sex ratios at birth, recent research has shown this association to exist among poor Hispanics. My dissertation used data from a national sample, 2002 National Survey of Family Growth. The results showed that women in China and South Korea who had a daughter instead of a son as their first child had a higher hazard of having a second birth as expected. Moreover, the results showed that the hazard ratio of having a third birth for Chinese and South Korean women was almost four and five times more, respectively. As expected, the hazard ratios for the U.S. were not significant and thus did not support the hypothesis. And the more educated women who had a daughter(s) instead of a son(s) as their previous child(ren) were less likely to have a second birth, but not in the third birth. This means women’s education apparently does not reduce son preference in the case of the third birth. Thus, women’s education apparently has limited or no influence on the childbearing decision where son preference is strong. Third, Hispanic women with low socioeconomic status did not have a significant hazard ratio of having a higher order birth. Accordingly, the dissertation does not find any statistical evidence of American son preference at the national level.
56

Son preference and fertility in China, South Korea, and the United States

Min, Ho Sik 15 May 2009 (has links)
The goal of this dissertation is to contribute in three ways to the literature on son preference and fertility through a comparative perspective. First, I examine the impact of son preference on fertility in China and South Korea compared with the United States. The impact that a female birth has on the likelihood of a woman having another birth is of the most concern: Women who have one or two daughter(s) as previous child(ren) are expected to be more likely to experience the hazard of having a second or a third birth. Second, my dissertation attempts to examine the effects of women’s status on son preference if women’s education reduces son preference. Third, my dissertation examines son preference and fertility in the U.S. Even though the U.S. has never shown son preference regarding sex ratios at birth, recent research has shown this association to exist among poor Hispanics. My dissertation used data from a national sample, 2002 National Survey of Family Growth. The results showed that women in China and South Korea who had a daughter instead of a son as their first child had a higher hazard of having a second birth as expected. Moreover, the results showed that the hazard ratio of having a third birth for Chinese and South Korean women was almost four and five times more, respectively. As expected, the hazard ratios for the U.S. were not significant and thus did not support the hypothesis. And the more educated women who had a daughter(s) instead of a son(s) as their previous child(ren) were less likely to have a second birth, but not in the third birth. This means women’s education apparently does not reduce son preference in the case of the third birth. Thus, women’s education apparently has limited or no influence on the childbearing decision where son preference is strong. Third, Hispanic women with low socioeconomic status did not have a significant hazard ratio of having a higher order birth. Accordingly, the dissertation does not find any statistical evidence of American son preference at the national level.
57

Empirical Examination of the Ex ante and Ex post Determinants of the ICT Adoption

Cheng, kai-yun 13 July 2004 (has links)
Abstract This article uses the plant-level data of Taiwan manufacturing industry to study the determinants in explaining the timing of information and communication technologies (ICTs) adoption. This paper then investigates whether there exists any difference in determining the utilization of ICTs among high-tech industries and traditional industries. We find size variable has the most significant effect while there appears a different impact in different industries.
58

Risk analysis of coastal flooding due to distant tsunamis

Gica, Edison. January 2005 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references (leaves 410-414).
59

Moral Hazard in den Finanzierungsbeziehungen des Internationalen Währungsfonds?

Barnert, Merten January 2009 (has links)
Zugl.: Greifswald, Univ., Diss., 2009
60

Evaluation of field data and 3D modelling for rockfall hazard analysis.

Vick, Louise Mary January 2015 (has links)
The Canterbury Earthquake Sequence (CES) of 2010-2011 produced large seismic moments up to Mw 7.1. These large, near-to-surface (<15 km) ruptures triggered >6,000 rockfall boulders on the Port Hills of Christchurch, many of which impacted houses and affected the livelihoods of people within the impacted area. From these disastrous and unpredicted natural events a need arose to be able to assess the areas affected by rockfall events in the future, where it is known that a rockfall is possible from a specific source outcrop but the potential boulder runout and dynamics are not understood. The distribution of rockfall deposits is largely constrained by the physical properties and processes of the boulder and its motion such as block density, shape and size, block velocity, bounce height, impact and rebound angle, as well as the properties of the substrate. Numerical rockfall models go some way to accounting for all the complex factors in an algorithm, commonly parameterised in a user interface where site-specific effects can be calibrated. Calibration of these algorithms requires thorough field checks and often experimental practises. The purpose of this project, which began immediately following the most destructive rupture of the CES (February 22, 2011), is to collate data to characterise boulder falls, and to use this information, supplemented by a set of anthropogenic boulder fall data, to perform an in-depth calibration of the three-dimensional numerical rockfall model RAMMS::Rockfall. The thesis covers the following topics: • Use of field data to calibrate RAMMS. Boulder impact trails in the loess-colluvium soils at Rapaki Bay have been used to estimate ranges of boulder velocities and bounce heights. RAMMS results replicate field data closely; it is concluded that the model is appropriate for analysing the earthquake-triggered boulder trails at Rapaki Bay, and that it can be usefully applied to rockfall trajectory and hazard assessment at this and similar sites elsewhere. • Detailed analysis of dynamic rockfall processes, interpreted from recorded boulder rolling experiments, and compared to RAMMS simulated results at the same site. Recorded rotational and translational velocities of a particular boulder show that the boulder behaves logically and dynamically on impact with different substrate types. Simulations show that seasonal changes in soil moisture alter rockfall dynamics and runout predictions within RAMMS, and adjustments are made to the calibration to reflect this; suggesting that in hazard analysis a rockfall model should be calibrated to dry rather than wet soil conditions to anticipate the most serious outcome. • Verifying the model calibration for a separate site on the Port Hills. The results of the RAMMS simulations show the effectiveness of calibration against a real data set, as well as the effectiveness of vegetation as a rockfall barrier/retardant. The results of simulations are compared using hazard maps, where the maximum runouts match well the mapped CES fallen boulder maximum runouts. The results of the simulations in terms of frequency distribution of deposit locations on the slope are also compared with those of the CES data, using the shadow angle tool to apportion slope zones. These results also replicate real field data well. Results show that a maximum runout envelope can be mapped, as well as frequency distribution of deposited boulders for hazard (and thus risk) analysis purposes. The accuracy of the rockfall runout envelope and frequency distribution can be improved by comprehensive vegetation and substrate mapping. The topics above define the scope of the project, limiting the focus to rockfall processes on the Port Hills, and implications for model calibration for the wider scientific community. The results provide a useful rockfall analysis methodology with a defensible and replicable calibration process, that has the potential to be applied to other lithologies and substrates. Its applications include a method of analysis for the selection and positioning of rockfall countermeasure design; site safety assessment for scaling and demolition works; and risk analysis and land planning for future construction in Christchurch.

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