Seagrasses are extremely productive coastal plant communities that serve as habitat for various types of marine and estuarine fauna and provide numerous ecosystem services. Seagrass meadows around the world have become threatened by environmental and anthropogenic pressures such as altered hydrologic regimes, physical disturbances, and eutrophication. Monitoring programs that provide high-resolution information and document changes in cover, morphometric characteristics, species composition, and tissue nutrient content across large spatial scales are critical in global conservation and management efforts. In an attempt to address the uncertainties regarding the current distribution and condition of seagrasses in the southwest Gulf of Mexico, I conducted annual sampling from 2011-2013 to examine seagrass cover and condition at 558 permanent stations. Sampling occurred in three regions of the Texas coast: the Coastal Bend (CB), Upper Laguna Madre (ULM), and Lower Laguna Madre (LLM), which together comprise over 94% of the seagrasses in Texas. Significant trends in seagrass coverage and tissue elemental composition were highly location- and species-specific. In the CB, I did not observe significant changes in seagrass cover and no spatial patterns in tissue nitrogen (N) or phosphorus (P) were apparent. However, I observed a species shift in the northern ULM, where significant decreases in Syringodium filiforme cover were coupled with significant increases in Halodule wrightii cover. Long-term salinity records at four stations throughout the study area suggest that S. filiforme mortality in the ULM in 2013 was a product of an extended period of high salinity (> 55) that began in late 2012. In LLM, there were significant increases in H. wrightii cover in the north and significant decreases in T. testudinum cover in the south, which cannot be explained based on underwater light levels, salinity, or nutrient availability. Both H. wrightii and T. testudinum displayed lower C:N, C:P, and N:P ratios, along with enriched δ¹⁵N signatures nearest urban areas, particularly in the LLM. This study illustrates the value of integrating rapid-assessment field sampling and rigorous statistical and spatial analysis into a large-scale seagrass monitoring program to uncover patterns in seagrass community structure. I detected significant trends in seagrass coverage and condition across multiple spatial and temporal scales, including a massive species replacement that coincided with a prolonged period of hypersaline conditions.

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Homogenization of monthly temperature data in BC is performed for 310 monthly maximum temperature series and 307 minimum temperature series from three networks: BC Hydro, BC Ministry of Forests Land Natural Resource Operations and Rural Development (Wildfire Management Branch) and the BC Ministry of Transportation and Infrastructure. The homogenization procedure is based on a penalized maximum t-test with mean-adjustment to detect inhomogeneities and make adjustments to the data. Before homogenization, quality control is performed on 797 stations at the daily time step. Trends at each location, in three sub-regions and across the province are analyzed based on resulting homogenized PCIC monthly temperature products. In order to measure the influence homogenization has on trends and validate the trends results calculated from the PCIC homogenized datasets, climate trends derived from the PCIC homogenized dataset are compared to those calculated from PCIC datasets without the homogenization and those from the homogenized temperature products existing in BC from ECCC respectively. The brief trend analysis components are introduced as follows. Trends before and after homogenization are compared for the averaged time series within three sub-regions based on PCIC station data. Trends based on homogenized PCIC stations and AHCCD stations are also compared. In addition, spatial patterns of trends over BC are analyzed based on PCIC gridded datasets, and compared with those of CANGRD. Homogenization results show that 92 out of 310 stations (29.6%) for maximum temperature and 75 out of 307 stations (24.4%) for minimum temperature have no detected changepoint, which means they appear to be homogenous. BCH has the highest portion of stations with changepoints, with 73.8% and 60.7% for maximum and minimum temperature, whereas FLNRO_WMB has the lowest portion, with 10.5% for Tmax and 27.3 % for Tmin. 80 and 81 stations have sufficient data for Tmax and Tmin variable have been analyzed for single station trend over 1990-2014. Comparing with the trends before homogenization, trends derived from homogenized PCIC stations have similar sign but smaller magnitude in general. The single station trend results are in good agreement with results of AHCCD. Spatial patterns of trends that are based on the interpolated PCIC stations also agree well with those based on CANGRD products. Warming trends predominate. Most of the seasons have distinctive positive trends across the province with exception of spring and some seasons over Vancouver Island. / Graduate

Streamflow in Western North America (WNA) has been experiencing pronounced changes in terms of volume and timing over the past century, primarily driven by natural climate variability and human-induced climate changes. This thesis advances on previous work by revealing the most recent streamflow changes in WNA using a comprehensive suite of classical hydrometric methods along with novel Deep Learning (DL) based approaches for change detection and classifica- tion. More than 500 natural streams were included in the analysis across western Canada and the United States. Trend analyses based on the Mann-Kendall test were conducted on a wide selection of classic hydrometric indicators to represent varying aspects of streamflow over 43 years from 1979 to 2021. A general geograph- ical divide at approximately 46◦N degrees latitude indicates that total streamflow is increasing to the north while declining to the south. Declining late summer flows (July–September) were also widespread across the WNA domain, coinciding with an overall reduction in precipitation. Some changing patterns are regional specific, including: 1) increased winter low flows at high latitudes; 2) earlier spring freshet in Rocky Mountains; 3) increased autumns flows in coastal Pacific North- west; and 4) dramatic drying in southwestern United States. In addition to classic hydrometrics, trend analysis was performed on Latent Features (LFs), which were extracted by Variation AutoEncoder (VAE) from raw streamflow data and are considered “machine-learned hydrometrics”. Some LFs with direct hydrological implications were closely associated with the classical hydrometric indicators such as flow quantity, seasonal distribution, timing and magnitude of freshet, and snow- to-rain transition. The changing patterns of streamflows revealed by LFs show direct agreement with the hydrometric trends. By reconstructing hydrographs from select LFs, VAE also provides a mechanism to project changes in streamflow patterns in the future. Furthermore, a parametric t-SNE method based on DL technology was developed to visualize similarity among a large number of hydro- graphs on a 2-D map. This novel method allowed fast grouping of hydrologically similar rivers based on their flow regime type and provides new opportunities for streamflow classification and regionalization. / Thesis / Doctor of Philosophy (PhD)

Web pages are typically comprised of different kinds of visual elements such as menus, headers and footers. To improve user experience, eye tracking has been widely used to investigate how users interact with such elements. In particular, eye movement sequences, called scanpaths, have been analysed to understand the path that people follow in terms of these elements. However, individual scanpaths are typically complicated and they are related to specific users, and therefore any processing done with those scanpaths will be specific to individuals and will not be representative of multiple users. Therefore, those scanpaths should be clustered to provide a general direction followed by users. This direction will allow researchers to better understand user interactions with web pages, and then improve the design of the pages accordingly. Existing research tends to provide a very short scanpath which is not representative for understanding user behaviours. This thesis introduces a new algorithm for clustering scanpaths, called Scanpath Trend Analysis (STA). In contrast to existing research, in STA, if a particular element is not shared by all users but it gets at least the same attention as the fully shared elements, it is included in the resulting scanpath. Thus, this algorithm provides a richer understanding of how users interact with web pages. The STA algorithm was evaluated with a series of eye tracking studies where the web pages used were automatically segmented into their visual elements by using different approaches. The results show that the outputs of the STA algorithm are significantly more similar to the inputted scanpaths in comparison with the outputs of other existing work, and this is not limited to a particular segmentation approach. The effects of the number of users were also investigated on the STA algorithm as the number of users required for scanpath analysis has not been studied in depth in the literature. The results show the possibility to reach the same results with a smaller group of users. The research presented in this thesis should be of value to eye tracking researchers, to whom the STA algorithm has been made available to analyse scanpaths, and to behaviour analysis researchers, who can use the algorithm to understand user behaviours on web pages, and then design, develop and present the pages accordingly.

This thesis is an investigation of identity theft, although not a new crime it has recently attracted public concern. This concern has led to both federal and state governments to establish new laws to provide increased protection. Government agencies and the media have warned the public that an individual's social security number and other personal information are the tools that unscrupulous criminals can use to gain access to an identity. Once your identity is assumed criminals can use that new identity to obtain goods and services freely available in this world of instant credit lines. The purpose of this study is to examine the magnitude and characteristics of identity theft. The objective is to determine if government official's claims and the media's portrayal of the substantial rise in identity theft incidents are supported empirically. The data for this study comes from police records located in one southern-metropolitan city; from this two separate data sets were drawn. A case study methodology was selected for this project. The results indicate that the identity theft trend is different than the trends for other theft related offenses -- credit card fraud, check fraud, robbery and motor vehicle theft. The data suggest that identity theft is increasing more rapidly than the other theft orientated offenses. However, future research should be conducted to help determine if the trend found in this study is a more a reflection of criminal behavior then of changes in reporting. Additionally, the available literature on identity theft suggested that attaining an arrest for identity theft is especially difficult. The empirical evidence found in this study is mixed on this point. Finally, the demographic characteristics of identity thieves in the area of study do not conform to other economically motivated offenders. African American female offenders make up a significantly large proportion of offenders. Determining the cause of these patterns would at this point be premature, but the existence of patterns warrants further research. In conclusion, this study finds support for the expressed belief by media, private organizations, and government officials that there is greater reporting and recoding of identity theft.

Ovarian follicles in women are fluid-filled structures in the ovary that contain oocytes (eggs). A dominant follicle is physiologically selected and ovulates during the menstrual cycle. We examined the echotexture in ultrasonographic images of the follicle wall of dominant ovulatory follicles in women during natural menstrual cycles and dominant anovulatory follicles which developed in women using oral contraceptives (OC). Texture features of follicle wall regions of both ovulatory and anovulatory dominant follicles were evaluated over a period of seven days before ovulation (natural cycles) or peak estradiol concentrations (OC cycles). Differences in echotexture between the two classes of follicles were found for two co-occurrence matrix derived texture features and two edge-frequency based texture features. Co-occurrence energy and homogeneity were significantly lower for ovulatory follicles while edge density and edge contrast were higher for ovulatory follicles. In the each feature space, the two classes of follicle were adequately separable.</p><p>This thesis employed several statistical approaches to analyses of texture features, such as plotting method and the Mann-Kendall method. A distinct change of feature trend was detected 3 or 4 days before the day of ovulation for ovulatory follicles in the two co-occurrence matrix derived texture features and two edge-frequency-based texture features. Anovulatory follicles, exhibited the biggest variation of the feature value 3 or 4 days before the day on which dominant follicles developed to maximum size. This discovery is believed to correspond to the ovarian follicles responding to system hormonal changes leading to presumptive ovulation.</p>

Ovarian follicles in women are fluid-filled structures in the ovary that contain oocytes (eggs). A dominant follicle is physiologically selected and ovulates during the menstrual cycle. We examined the echotexture in ultrasonographic images of the follicle wall of dominant ovulatory follicles in women during natural menstrual cycles and dominant anovulatory follicles which developed in women using oral contraceptives (OC). Texture features of follicle wall regions of both ovulatory and anovulatory dominant follicles were evaluated over a period of seven days before ovulation (natural cycles) or peak estradiol concentrations (OC cycles). Differences in echotexture between the two classes of follicles were found for two co-occurrence matrix derived texture features and two edge-frequency based texture features. Co-occurrence energy and homogeneity were significantly lower for ovulatory follicles while edge density and edge contrast were higher for ovulatory follicles. In the each feature space, the two classes of follicle were adequately separable.</p><p>This thesis employed several statistical approaches to analyses of texture features, such as plotting method and the Mann-Kendall method. A distinct change of feature trend was detected 3 or 4 days before the day of ovulation for ovulatory follicles in the two co-occurrence matrix derived texture features and two edge-frequency-based texture features. Anovulatory follicles, exhibited the biggest variation of the feature value 3 or 4 days before the day on which dominant follicles developed to maximum size. This discovery is believed to correspond to the ovarian follicles responding to system hormonal changes leading to presumptive ovulation.</p>

ABSTRACT Although the fractions of station-days that the Pollutant Standard Index (PSI) exceed 100 (also referring to the episodes) in Kaohsiung City showed a decline trend from about 10.3% in 1995 to about 5.5% in 2002, the percentage of particulate PM10 events showed a increase trend: from 1.0 % in 2002 to 2.9 % in 2004. This study first statistically summarized the trends of PM10 concentrations using box plots for four air-quality monitoring stations in Kaohsiung during the period of 1997 to 2004, together with the t-test and F-test. The Comprehensive Air Quality Model with extensions (CAMx model) was then applied to analyze the source and the cause of the PM10 events. The monthly averages of PM10 concentrations at four air-quality monitoring stations were 72.9 ¡V 81.7 £gg/m3 during the period of 1997 to 2004, highest at Hsiung-Kong and lowest at Nan-Chie. The long-term trend analyses show slightly decline results for yearly-averaged PM10 concentrations (1.05% at Nan-Chie, 1.38% at Tzuo-Yin, 1.51% at Chien-Chin, and 1.91% at Hsiung-Kong). During 1997 to 2004, the PM10 episodes occurred most frequently, while the numbers of PM10 episodes decreased from south to north (i.e., Hsiung-Kong > Chien-Chin > Tzuo-Yin > Nan-Chie). The statistical tests using t-test for the mean and F-test for the variance with 95% confidence level show that the probability that the hourly PM10 concentrations differ insignificantly among the four stations is only about 42%. That is, the spatial difference of pollutant concentrations among four air-quality monitoring stations is rather significant in Kaohsiung. The CAMx simulations show that contributions to ambient PM10 from stationary source is about 38.9% (NOx: 24.7%; SO2: 14.2%), 8.8% from mobile source (NOx: 7.4%; SO2: 1.4%), and 0.9% from fugitive emissions (SO2: 0.9%) in Kaohsiung. The contributions to ambient PM10 from the emissions in Kaohsiung Harbor are about 3.5%. Keywords: Particulate matter, Trend analysis, Statistical test, CAMx model.

Title from PDF of title page. / Document formatted into pages; contains 70 pages. / Thesis (MA)--University of South Florida, 2003. / Includes bibliographical references. / Text (Electronic thesis) in PDF format. / ABSTRACT: This thesis is an investigation of identity theft, although not a new crime it has recently attracted public concern. This concern has led to both federal and state governments to establish new laws to provide increased protection. Government agencies and the media have warned the public that an individual's social security number and other personal information are the tools that unscrupulous criminals can use to gain access to an identity. Once your identity is assumed criminals can use that new identity to obtain goods and services freely available in this world of instant credit lines. The purpose of this study is to examine the magnitude and characteristics of identity theft. The objective is to determine if government official's claims and the media's portrayal of the substantial rise in identity theft incidents are supported empirically. / ABSTRACT: The data for this study comes from police records located in one southern-metropolitan city; from this two separate data sets were drawn. A case study methodology was selected for this project. The results indicate that the identity theft trend is different than the trends for other theft related offenses -- credit card fraud, check fraud, robbery and motor vehicle theft. The data suggest that identity theft is increasing more rapidly than the other theft orientated offenses. However, future research should be conducted to help determine if the trend found in this study is a more a reflection of criminal behavior then of changes in reporting. Additionally, the available literature on identity theft suggested that attaining an arrest for identity theft is especially difficult. The empirical evidence found in this study is mixed on this point. / ABSTRACT: Finally, the demographic characteristics of identity thieves in the area of study do not conform to other economically motivated offenders. African American female offenders make up a significantly large proportion of offenders. Determining the cause of these patterns would at this point be premature, but the existence of patterns warrants further research. In conclusion, this study finds support for the expressed belief by media, private organizations, and government officials that there is greater reporting and recoding of identity theft. / System requirements: World Wide Web browser and PDF reader. / Mode of access: World Wide Web.