The distribution of mountain permafrost is generally modeled using a combination of statistical techniques and empirical variables. Such models, based on topographic, climatic and geomorphological predictors of permafrost, have been widely used to estimate the spatial distribution of mountain permafrost in North America and Europe. However at present, little knowledge about the distribution and characteristics of mountain permafrost is available for the Andes. In addition, the effects of climate change on slope stability and the hydrological system, and the pressure of mining activities have increased concerns about the knowledge of mountain permafrost in the Andes. In order to model permafrost distribution in the semi-arid Chilean Andes between ~29°S and 32°S, an inventory of rock glaciers is carried out to obtain a variable indicative of the presence and absence of permafrost conditions. Then a Linear Mixed-Effects Model (LMEM) is used to determine the spatial distribution of Mean Annual Air Temperature (MAATs), which is then used as one of the predictors of permafrost occurrence. Later, a Generalized Additive Model (GAM) with a logistic link function is used to predict permafrost occurrence in debris surfaces within the study area. Within the study area, 3575 rock glaciers were inventoried. Of these, 1075 were classified as active, 493 as inactive, 343 as intact and 1664 as relict forms, based on visual interpretation of satellite imagery. Many of the rock glaciers (~60-80%) are situated at positive MAAT, and the number of rock glaciers at negative MAAT greatly decreases from north to south. The results of spatial temperature distribution modeling indicated that the temperature changes by -0.71°C per each 100 m increase in altitude, and that there is a 4°C temperature difference between the northern and southern part of the study area. The altitudinal position of the 0°C MAAT isotherm is situated at ~4250 m a.s.l. in the northern (29°S) section and drops latitudinally to ~4000 m a.s.l. in the southern section (32°S) of the study area. For permafrost modeling purposes, 1911 rock glaciers (active, inactive and intact forms) were categorized into the class indicative of permafrost presence and 1664 (relict forms) as non-permafrost. The predictors MAAT and Potential Incoming Solar Radiation (PISR) and their nonlinear interaction were modeled by the GAM using LOESS smoothing function. A temperature offset term was applied to reduce the overestimation of permafrost occurrence in debris surface areas due to the use of rock glaciers as permafrost proxies. The dependency between the predictor variables shows that a high amount of PISR has a greater effect at positive MAAT levels than in negative ones. The GAM for permafrost distribution achieved an acceptable discrimination capability between permafrost classes (area under the ROC curve ~0.76). Considering a permafrost probability score (PPS) ≥ 0.5 and excluding steep bedrock and glacier surfaces, mountain permafrost can be potentially present in up to about 6.8% (2636 km2) of the study area, whereas with a PPS ≥ 0.75, the potential permafrost area decreases to 2.7% (1051 km2). Areas with the highest PPS are spatially concentrated in the north section of the study area where altitude rises considerably (the Huasco and Elqui watersheds), while permafrost is almost absent in the southern section where the topography is considerably lower (Limarí and Choapa watersheds). This research shows that the potential mountain permafrost distribution can be spatially modeled using topoclimatic information and rock glacier inventories. Furthermore, the results have provided the first local estimation of permafrost distribution in the semi-arid Chilean Andes. The results obtained can be used for local environmental planning and to aid future research in periglacial topics.

In this thesis Generalized Additive Neural Networks (GANNs) are studied in the context of predictive Data Mining. A GANN is a novel neural network implementation of a Generalized Additive Model. Originally GANNs were constructed interactively by considering partial residual plots. This methodology involves subjective human judgment, is time consuming, and can result in suboptimal results. The newly developed automated construction algorithm solves these difficulties by performing model selection based on an objective model selection criterion. Partial residual plots are only utilized after the best model is found to gain insight into the relationships between inputs and the target. Models are organized in a search tree with a greedy search procedure that identifies good models in a relatively short time. The automated construction algorithm, implemented in the powerful SAS® language, is nontrivial, effective, and comparable to other model selection methodologies found in the literature. This implementation, which is called AutoGANN, has a simple, intuitive, and user-friendly interface. The AutoGANN system is further extended with an approximation to Bayesian Model Averaging. This technique accounts for uncertainty about the variables that must be included in the model and uncertainty about the model structure. Model averaging utilizes in-sample model selection criteria and creates a combined model with better predictive ability than using any single model. In the field of Credit Scoring, the standard theory of scorecard building is not tampered with, but a pre-processing step is introduced to arrive at a more accurate scorecard that discriminates better between good and bad applicants. The pre-processing step exploits GANN models to achieve significant reductions in marginal and cumulative bad rates. The time it takes to develop a scorecard may be reduced by utilizing the automated construction algorithm. / Thesis (Ph.D. (Computer Science))--North-West University, Potchefstroom Campus, 2006.

This study investigated long-term (1961-2008) changes in albacore (Thunnus alalunga) abundance and distribution in relation to local environmental and large-scale climate indices in the Northeastern Pacific using time series and spatial analyses. Prior to the time series analysis, a wavelet analysis was conducted to examine nonrandom patterns of cyclical variability which revealed that monthly and annual time scales had the highest non-random variability. Thus, the time series analysis was done at these two scales using non-linear generalized additive models (GAMs) and threshold GAMs. At the monthly scale, sea surface temperature (SST) was found to be the variable with the strongest (positive) association to albacore catch per unit effort (CPUE). This association was likely driven by the seasonal migrations of juvenile albacore into and out of the U.S. coastal waters. At the yearly time scale over large geographical areas, the SST association broke down, and the scalar wind speed cubed (an indicator of mixed layer depth) at a five year lag became the dominant variable. The scalar wind speed cubed index explained 65% of the variability and was highly significant, even after adjusting for multiple tests (Bonferroni corrected P-value<0.001). These results suggest that a deeper mixed layer in the Northeastern Pacific may provide favorable foraging habitat for juvenile (mostly age 3) albacore, resulting in successful growth, spawning, and recruitment into the fishery in later years. This mixed layer depth association could help managers and stock assessment groups in their efforts to integrate environmental factors into the estimate of albacore population size. The spatial/spatio-temporal analyses involved modeling the CPUE with four competing GAM formulations, each representative of a different hypotheses for albacore distribution: 1) spatial, 2) spatial and environmental (SST, PDO, and MEI), 3) spatially variant, and 4) nonstationary, as indicated by the North Pacific regime shift of 1977. Results indicate that SST had a predominantly positive but spatially-variable effect on albacore CPUE, while the PDO had a negative overall effect. Specifically, CPUE was found to increase with increased SST, particularly off of Oregon and Washington. These results imply that if ocean temperatures continue to increase, west coast communities reliant on commercial albacore fisheries are likely to be negatively impacted in the southern areas but positively benefited in the northern areas, where current albacore landings are highest. / Graduation date: 2012

This research studies the social support in a group of adult persons with HIV: 14 women and 41 men between 18 and 58 years of age, from medium- low social economic status that appeal to state health centers, non government entities and mutual support groups of Lima. The resultsof perceived social support, effective social support, social support satisfaction and social support need ha ve been correlated with variables age, sex, diagnostic time, presence of symptoms associated lo H!V, participation in a mutual support group, sex and sexual orientation(heterosexual males, men that have sex with other men and heterosexual women).The results showed that the social support indexes behaved differently according to weather they participated in a mutual support group or not, according to sex, according to sex and sexual orientation. Also, the need for social support rate varies according to diagnostic time. / Se investiga el soporte social en un grupo de adultos con V!H: catorce mujeres y cuarenta y un hombres. de entre 18 y 58 años. de estrato socioeconómico bajo y medio bajo que acuden a centros de salud estatales, organismos no gubernamentales y grupos de ayuda mutua (GAM) de Lima. Se correlacionaron los resultados descriptivos de los índices soporte social percibido, soporte social efectivo, satisfacción con el soporte y necesidad de soporte con las variables edad, sexo, tiempo de diagnóstico, presencia o no de síntomas asociados al VIH, participación o no en un GAM y orientación sexual (hombres heterosexuales, hombres que tienen sexo ton otros hombres (HSH) y mujeres heterosexuales). Se encontró que los índices del soporte social se comportan diferente según se pertenezca a un GAM o no, según el sexo, según la orientación sexualy el sexo. Asimismo, el índice necesidad de soporte varía según el tiempo de diagnóstico.

Superficial information of the civil wars in Aceh, Indonesia and Sri Lanka creates the idea that both conflicts were in similar situations when they were hit by the Indian Ocean tsunami in 2004. It thus seems surprising that in the wake of the tsunami, the Free Aceh Movement and the Government of Indonesia signed a peace agreement, while the Liberation Tigers of Tamil Eelam and the Government of Sri Lanka returned to war. This thesis aims to explore what factors related to the tsunami contributed to this difference and whether rational choice theory can serve as an explanation for this difference. In order to find out, I conducted a qualitative comparative case study though the analysis of secondary documents. The results suggest that the factors that contributed to the difference can be divided into four broad themes: (1) the timing of the tsunami and thus the pre-disaster context; (2) the geographical situation and with that, the military impact; (3) the types of guerilla groups, including their abilities to rule, their access to financial capital and their strategic; (4) the role of the international community, which can be further divided into firstly, the geopolitical relevance of these countries, and secondly, internationalization, community engagement and separating the tsunami and conflict. I believe that rational choice theory explains the difference in outcome between the two conflicts very well. This theory assumes that people, given the circumstances, and in view of all the possible options, will act in line with the option that is expected to satisfy them most and minimize their losses. Applying this theory to the case studies of Aceh and Sri Lanka following the tsunami, it was appealing for the Free Aceh Movement to settle, but this was not the case for the Liberation Tigers of Tamil Eelam. As a result, the former chose to sign a peace agreement with the Government of Indonesia, whereas the latter chose to continue its fight against the Government of Sri Lanka.

No description available.

Species distribution maps can provide important information to focus conservation efforts and enable spatial management of human activities. Two sympatric marine predators, grey seals (Halichoerus grypus) and harbour seals (Phoca vitulina), have overlapping ranges but contrasting population dynamics around the UK; whilst grey seals have generally increased, harbour seals have shown significant regional declines. A robust analytical methodology was developed to produce maps of grey and harbour seal usage estimates with corresponding uncertainty, and scales of spatial partitioning between the species were found. Throughout their range, both grey and harbour seals spend the majority of their time within 50 km of the coast. The scalability of the analytical approach was enhanced and environmental information to enable spatial predictions was included. The resultant maps have been applied to inform consent and licensing of marine renewable developments of wind farms and tidal turbines. For harbour seals around Orkney, northern Scotland, distance from haul out, proportion of sand in seabed sediment, and annual mean power were important predictors of space-use. Utilising seal usage maps, a framework was produced to allow shipping noise, an important marine anthropogenic stressor, to be explicitly incorporated into spatial planning. Potentially sensitive areas were identified through quantifying risk of exposure of shipping traffic to marine species. Individual noise exposure was predicted with associated uncertainty in an area with varying rates of co-occurrence. Across the UK, spatial overlap was highest within 50 km of the coast, close to seal haul outs. Areas identified with high risk of exposure included 11 Special Areas of Conservation (from a possible 25). Risk to harbour seal populations was highest, affecting half of all SACs associated with the species. For 20 of 28 animals in the acoustic exposure study, 95% CI for M-weighted cumulative Sound Exposure Levels had upper bounds above levels known to induce Temporary Threshold Shift. Predictions of broadband received sound pressure levels were underestimated on average by 0.7 dB re 1μPa (± 3.3). An analytical methodology was derived to allow ecological maps to be quantitatively compared. The Structural Similarity (SSIM) index was enhanced to incorporate uncertainty from underlying spatial models, and a software algorithm was developed to correct for internal edge effects so that loss of spatial information from the map comparison was limited. The application of the approach was demonstrated using a case study of sperm whales (Physeter macrocephalus, Linneaus 1758) in the Mediterranean Sea to identify areas where local-scale differences in space-use between groups and singleton whales occurred. SSIM is applicable to a broad range of spatial ecological data, providing a novel tool for map comparison.

Running title: Personality and cyberbullying victimisation / Includes bibliographical references (leaves 104-120) / The aim of this study was to gain insight into the relationship between personality and cyberbullying victimisation using a sample of 107 adult participants. The participants were found using the social media site Facebook in particular and assessed by means of the Big Five Inventory and a cyberbullying measure developed by the researcher. The study also explored the relationship between personality and coping behaviours using the COPE Inventory. The study findings indicate that neuroticism and cyberbullying victimisation are correlated, albeit weakly, with the largest correlation being between neuroticism and online impersonation and harassment. In addition, the study found a weak correlation between openness to experience and online impersonation. Coping and personality were moderately correlated; with neurotic individuals and victims of cyberbullying often resorting to maladaptive coping strategies. These results may suggest that there are other, more significant risk factors in the cyberbullying field that merit further exploration, while the relationships highlighted in the study also require further investigation. / Psychology / M.A. (Psychology)