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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.
231

Time series study of urban rainfall suppression during clean-up periods

Geng, Jun 15 May 2009 (has links)
The effect on urban rainfall of pollution aerosols is studied both by data analysis and computational simulation. Our study examines data for urban areas undergoing decadal clean-up. We compare the annual precipitation between polluted sites and relatively clean sites through the time range before and during their clean-up periods to see how the air quality may affect the precipitation amount. By comparing the annual precipitation amount between two polluted sites with different elevations we demonstrate the role that elevation may play in rainfall suppression. Based on the data we collected, we built a model to analyze the relationship between air pollution aerosols and precipitation. Finally, we used a model of time dependent condensational aerosol growth to numerically study the relationship of air pollution aerosols and precipitation amount. Based on these results, we found a negative relationship of precipitation amount and air pollution amount; also, the simulation results clearly demonstrated that too many air pollution particles will deplete the water vapor and suppress further growth of condensation nuclei (CN) toward cloud condensation nuclei (CNN). This study supported the theoretical explanation on why air pollution could suppress urban rainfall.
232

A case study of an expert mathematics teacher's interactive decision-making system using physiological and behavioral time series data

Jensen, Deborah Larkey 17 February 2005 (has links)
The purpose of this exploratory case study was to describe an expert teacher’s decision-making system during interactive instruction using teacher self-report information, classroom observation data, and physiological recordings. Timed recordings of instructional interaction variables using an adapted Stallings Observation System were combined with simultaneous skin voltage measurements in time series analyses to describe observable and physiological elements of an expert teacher’s decision-making process. The mean and standard deviation of observable decision-action rates on teacher-identified “teaching days” were higher than the rates on “guiding” days. Bivariate time series analysis of decision-action rates and physiological response rates showed a significant positive relationship between the teacher’s decision-action rate and her physiological response rate on one teaching day. The positive relationship between the teacher’s decision-action rate and her physiological response rate was found to be context-dependent and related to the teaching strategy being used. High decision-action rates during direct instruction were associated with high physiological response rates compared to lower decision-action rates and physiological response rates while monitoring independent seatwork during a test. Correlation analysis of physiological response rates with time revealed slight, but statistically significant negative trends for four of the five observation days. Major features of the teacher’s decision-making system included focusing attention on academic instruction with the use of routines for managing students and materials to perform teaching tasks; both proactive and reactive improvisational decisions; and physiological events characteristic of autonomic nervous system activity during instructional sequences of high teacher-student interactivity. Damasio’s Somatic Marker Hypothesis (Damasio, 1999) is offered as an explanation for the generation of specific characteristics of the expert teacher’s instruction, such as the high frequency of decision-actions and automaticity of appropriate decisions.
233

Time series study of urban rainfall suppression during clean-up periods

Geng, Jun 10 October 2008 (has links)
The effect on urban rainfall of pollution aerosols is studied both by data analysis and computational simulation. Our study examines data for urban areas undergoing decadal clean-up. We compare the annual precipitation between polluted sites and relatively clean sites through the time range before and during their clean-up periods to see how the air quality may affect the precipitation amount. By comparing the annual precipitation amount between two polluted sites with different elevations we demonstrate the role that elevation may play in rainfall suppression. Based on the data we collected, we built a model to analyze the relationship between air pollution aerosols and precipitation. Finally, we used a model of time dependent condensational aerosol growth to numerically study the relationship of air pollution aerosols and precipitation amount. Based on these results, we found a negative relationship of precipitation amount and air pollution amount; also, the simulation results clearly demonstrated that too many air pollution particles will deplete the water vapor and suppress further growth of condensation nuclei (CN) toward cloud condensation nuclei (CNN). This study supported the theoretical explanation on why air pollution could suppress urban rainfall.
234

On Puiseux series and resolution graphs /

Neuerburg, Kent M. January 1998 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1998. / Typescript. Vita. Includes bibliographical references (leaf 93). Also available on the Internet.
235

Mixed portmanteau test for ARMA-GARCH models /

Sze, Mei Ki. January 2009 (has links)
Includes bibliographical references (p. 29-30).
236

Über die asymptotische Darstellung der Integrale linearer Differenzen-Gleichungen durch Potenzreihen

Erb, Theodor, January 1913 (has links)
Thesis (doctoral)--K. Ludwig-Maximilians-Universität zu München, 1913. / Vita.
237

On tests for threshold-type non-linearity in time series analysis

Ng, Man-wai. January 2001 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 71-74).
238

Untersuchungen zur Theorie der Folgen analytischer Funktionen

Jentzsch, Robert, January 1900 (has links)
Thesis (doctoral)--Friedrich-Wilhelms-Universität zu Berlin, 1914. / Vita. Includes bibliographical references.
239

Signal propagation modeling and optimization techniques for timing analysis

Tutuianu, Bogdan. January 2003 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2003. / Vita. Includes bibliographical references. Available also from UMI Company.
240

On Puiseux series and resolution graphs

Neuerburg, Kent M. January 1998 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1998. / Typescript. Vita. Includes bibliographical references (leaf 93). Also available on the Internet.

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