Este estudo apresenta, de forma sistemática, a importância da infraestrutura de mina a céu aberto, determinando as atividades principais dessa fase e os impactos e benefícios causados por alterações na forma de execução, medidos através de indicadores de produtividade e resultados financeiros. Algumas atividades principais como a reconfiguração das faces dos bancos de lavra pela aplicação comparativa de desempenho de trator de esteira e retroescavadeira; o estabelecimento de padrão para o dimensionamento das camadas estruturais e funcionais das estradas de mina; a mensuração dos benefícios da construção e manutenção das estradas, no desempenho dos caminhões e dos tratores de esteira, através de estudos de caso e demonstrar que a aplicação de técnicas adequadas modificam o resultado operacional. A metodologia utilizada aborda a relevância da infraestrutura e da frota de equipamentos auxiliares dentro do ciclo operacional, propondo uma aplicação correta e sistemática, baseada na demanda e nas atividades auxiliares que proporcionam condições operacionais para as atividades "que geram valor", suportando o cumprimento das metas estabelecidas no plano de produção. Os principais resultados obtidos vão desde a melhoria da segurança operacional, da imagem da empresa, do resultado financeiro, ao melhor aproveitamento dos recursos minerais, impactando diretamente a sustentabilidade do negócio. Através dos casos abordados neste trabalho, conclui-se que o desempenho da mineração a céu aberto é fortemente dependente do foco dado à infraestrutura de mina, ou seja: da qualidade das pistas, adequação das praças de carregamento, condição operacional de pilhas de estéril ou minério, drenagem superficial, dos métodos de trabalho e da disciplina operacional, gerando ganhos e/ou perdas que vão de unidades de porcentagem a várias vezes a capacidade do processo abordado. / This study presents, in a systematic way, the importance of the infrastructure in the open pit mining, determining the main activities of this operation and the impacts and benefits from changes implemented measured by operating productivity indicators and financial results. Some major activities such as the reconfiguration of the slope faces by the comparative performance of bulldozer and backhoe; the establishment of standards for the design of structural and functional layers of the mine haul roads; measure the benefits of the construction and maintenance of roads, the performance of trucks and bulldozers, through case studies show that the application of appropriate techniques can modify the operating result. The methodology addresses the importance of infrastructure and auxiliary equipment fleet in the operating cycle, proposing a correct and systematic application, based on demand and auxiliary activities that provide operating conditions for activities "that create value", supporting the achievement of the goals established in the production plan. The main results ranging from improved operational safety, company image, financial results, the best use of mineral resources, directly impacts on the business sustainability. Through the cases discussed in this work, it is concluded that the performance of the open pit mining is strongly dependent on the focus given to the mine infrastructure wich means, the quality of the tracks, adequacy of the loading spots, operating condition of waste dumps or ore bins, surface drainage, working methods and operational discipline, generating gains and/or losses ranging from small amounts to several times the capacity of the covered process.

Snake species are notoriously difficult to study in the field due to their cryptic natural-histories and secretive behaviors. Difficulties associated with detection present challenges estimating parameters including occupancy and abundance, as well as responses to habitat degradation. Our objectives were to use Passive Integrated Transponder (PIT) telemetry to enhance detection of Queensnakes (Regina septemvittata) as compared to traditional capture-mark-recapture (CMR) survey techniques and to examine occupancy and abundance of Queensnakes and Northern Watersnakes (Nerodia sipedon) in streams of differing levels of anthropogenic impact within Central Kentucky. During 2013, we captured Queensnakes and implanted them with PIT tags. We detected significantly more tagged snakes using PIT telemetry than visual surveys. We did not observe significant differences in numbers of snakes detected using PIT telemetry at different times of day. We observed relatively high site fidelity of individuals. During 2014, we conducted point-count surveys of Northern Watersnakes and Queensnakes in streams characterized as highly degraded and lightly impaired. We estimated occupancy and conditional abundance among site types. We did not observe significant differences in occupancy or abundance between historically highly-impacted sites and less-impacted sites. We were able to determine significance of some environmental variables influencing detection of snakes.

Indiana University-Purdue University Indianapolis (IUPUI) / Continued consumption of alcohol despite the knowledge of negative consequences is a hallmark of alcohol use disorder (AUD), yet much remains unknown about what motivates these behaviors. Compulsive drinking may require motivational resources that are not necessary when drinking in unchallenged conditions in order to counteract the addition of these negative consequences. Increased sensitivity to drug-paired stimuli via associative learning processes may provide this additional motivation. To evaluate if alcohol-paired stimuli enhance alcohol seeking, selectively bred crossed High Alcohol Preferring mice experienced Pavlovian conditioning procedures with an alcohol unconditioned stimulus. We hypothesized that after repeated pairings, alcohol cues would elicit seeking conditioned responses. Then, to determine if the motivation provided by these cues influenced responding, mice were trained to respond for alcohol and tested in the presence of alcohol cues. Finally, to test if alcohol-paired cues influence compulsive drinking, this same test was repeated with the addition of response-contingent footshock. We hypothesized the cue paired with alcohol would increase responding for alcohol in unchallenged conditions, but especially in challenged conditions, contributing to compulsivity. An auditory stimulus paired with alcohol did elicit enhanced seeking responses, but contrary to hypothesis, we observed no effect of these same cues on instrumental responding. To validate these findings, training and testing procedures must be optimized to ensure conditioning has properly occurred and compulsivity is being appropriately measured.

Ingeniero Civil de Minas / El objetivo del presente trabajo es medir el impacto que tiene la dilución en la planificación de minas cielo abierto, para cuerpos altamente estratificados y vetiformes. En la actualidad la industria minera ha alcanzado un punto donde el descubrimiento de nuevos yacimientos masivos tipo pórfido cuprífero se vuelve cada vez más rara. Por ello los yacimientos de vetas cobran cada vez mayor importancia en el negocio minero. Un desafío que presentan estos cuerpos es la incorporación de técnicas o practicas operacionales que permitan alcanzar una selectividad suficiente para volver rentable el proyecto, sin mencionar que en ciertos contextos geológicos las estructuras presentan contaminantes, por lo que incluso siendo rentable pueden existir problemas en etapas posteriores. Con este fin se debe tratar la dilución como un factor fundamental, tema que en la industria actual es poco estudiado. Para ello se cuenta con la siguiente metodología, mediante un estudio de un yacimiento de cobre modificado, que imita a uno autentico a escala real. Primero se lleva a cabo un estudio sobre los tipos de dilución, su impacto y formas de cuantificarla en la industria. Luego se generan escenarios con diferentes leyes medias en la roca caja, además de cuatro cambios de soporte, con el fin de verificar el impacto en un amplio espectro de casos. Se construye un indicador que evalúa la vecindad de cada bloque, estableciendo una categoría según el contacto existente para cada uno de los bloques del modelo. Después se calculan las proporciones de mineral en contacto con estéril, cuantificando así la cantidad de recursos susceptibles a diluirse. A continuación, se realiza la planificación a largo plazo, donde finalmente se recolectan los resultados de los casos propuestos y se analizan mediante indicadores técnicos y económicos claves. Se llega que, a medida que aumenta el tamaño de bloque, aumenta la categoría de mineral en contacto con estéril, reduciéndose así la cantidad de mineral sin riesgo de dilución y de la misma manera se reduce el estéril en contacto solo con estéril, aunque en menor proporción. Finalmente, aplicando restricciones de mezcla en la planificación, admitiendo un máximo de dilución permitido, se producen castigos al VAN del proyecto, llegando a un balance entre el riesgo de diluir el recurso y el valor del plan.

El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / Currently, in open-pit mining operations, the highest cost among all processes is that of transporting trucks, whether in fuel, roads, tires, or spare parts, among other factors. Therefore, this article proposes the use of the Six Sigma methodology of continuous improvement as a quality management tool to reduce the downtime of the truck fleet to obtain better productivity in operations. The results of the investigation in the case study allowed to visualize that with the election of an optimal fleet appropriate for the conditions given in a mining project, the values of productivity and efficiency improve considerably. This is reflected in a better use of the machinery and in the reduction of unproductive times.

El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / Presplitting is a controlled-blasting technique with applications in open-pit mines. The main purpose of this technique is to prevent and control overbreaks caused by excessive vibrations due to blasting. This technique is especially effective in controlling overbreaks because it provides a separation surface between the main blasting pattern and the walls of the final slopes. The drilling mesh and loading conditions in the drill are designed in this study by considering the uncontrollable variables of the rock mass as important factors. The proposed model for the presplitting optimization process helps to optimize controlled-blasting designs. The main idea of the proposal is to develop a model that includes the most relevant processes, as well as the most suitable parameters for an efficient design. Copyright 2019.

Indiana University-Purdue University Indianapolis (IUPUI) / This clinical study investigated the efficacy of the new LED LCU technology when compared to that of the QTH LCU by evaluating retention and wear of Clinpro (3M ESPE) sealant material over six months of function. This study was designed as a split mouth, randomized clinical study. Sealants were placed and polymerized on contralateral teeth of 35 patients, 33 of which successfully completed the study. The sealants were evaluated for clinical retention at baseline, three months, and six months by two evaluators. For the wear analysis, the area of the sealant wear at six months is reported. Nine pairs of molars and 22 pairs of premolar teeth were used. This sample size is smaller than the original sample used for clinical evaluation, because a number of the baseline impressions had to be discarded due to poor impression quality. Subsequent impressions were taken at three months, and six months. Epoxy replicas were made from the impressions and the occlusal surface of each replica was digitized using SigmaScan software. A cummulative legit model was applied to the clinical data, and a linear model was applied to the wear analysis. The results for clinical retention over the six months of function were as follows. At Baseline, for the QTH, 97.3 percent of the teeth received an Alpha score; 2.7 percent received a score of B. For the LED, 87.7 percent received a score of A; 12.3 percent received a score of B. At three months follow-up, for the QTH, 93.1 percent received a score of A; 6.9 percent received a score of B. For the LED, 86.1 percent received a score of A; 12.5 percent received a score of B, and 1.14 percent received a score of C. At six months follow-up, for QTH; 91.7 percent received a score of A; 8.3 percent received a score of B. For the LED, 83.3 percent received a score of A; 15.3 percent received a score of B, and 1.14 percent received a score of C. The hypothesis was that there would be no significant difference in clinical retention and wear of Clinpro's sealant polymerized with the QTH or the LED light sources over six months of function. Based on the results of this clinical study, the following conclusions can be made: 1) At baseline, Clinpro's sealant polymerized with QTH light source showed marginally significant better retention than LED light source (p-value 0.05001). 2) There was no significant difference between light sources for sealant clinical retention at three-month and six-month follow up visits. 3) Wear analysis resulted in marginally significant more wear for molar sealants polymerized with LED LCU (p-value 0.0755). 4) Wear analysis showed no significant difference for premolar sealants polymerized with either light source.

In order to be compliant with the Basel regulations, banks need to compute two probabilities of default (PDs): point-in-time (PIT) and through-the-cycle (TTC). The aim is to explain fluctuations in the rating system, which are expected to be affected by systematic and idiosyncratic factors. Being able to, in an objective manner, determine whether the rating system is taking the business cycle - i.e the systematic factors - into account when assigning a credit rating to an obligor is useful in order to evaluate PD-models. It is also necessary for banks in order to use their own risk parameters and models instead of standardized models, which is desirable for most banks as it could lower capital requirements. This thesis propose a new measure for the degree of PIT-ness. This measure aims to be especially useful when examining a low default portfolio. The proposed measure is built on a markovian approach of the credit rating system. In order to find a suitable measure for a low default portfolio, the proposed measure takes into account credit rating migrations, the seasonal component of the business cycle and time series analysis. An analysis were performed between two different credit portfolios in order to interpret results. The results demonstrated that the degree of PIT-ness was lower in a low default portfolio in comparison with a sampled portfolio which displayed a greater amount of rating migrations with a larger magnitude. The importance of considering relevant macroeconomic variables to represent the business cycle was mentioned amongst the most important factors to consider in order to receive reliable results given the proposed measure. / För att uppfylla Basel regelverken behöver banker beräkna två sannolikheter för fallissemang (PD): point-in-time (PIT) och through-the-cycle (TTC). Målet är att förklara fluktuationer i betygssystemet, som förväntas påverkas av systematiska och idiosynkratiska faktorer. Att på ett objektivt sätt kunna avgöra om betygssystemet tar hänsyn till affärscykeln - dvs de systematiska faktorerna - när man tilldelar en kredittagare ett kreditbetyg är användbart för att utvärdera PD-modeller. Detta är också nödvändigt för att banker ska få använda sina egna riskparametrar och modeller istället för standardiserade modeller, vilket är önskvärt för de flesta banker eftersom det kan sänka kapitalkraven. Denna avhandling föreslår ett nytt mått för att mäta graden av PIT-ness. Detta mått syftar till att vara särskilt användbart när man utvärderar en kreditportfölj med få fallissemang. Det föreslagna måttet är byggt på en Markov tillämpning på kreditbetygssystemet. För att hitta ett lämpligt mått för en kreditportfölj med få fallissemang, tar det föreslagna måttet hänsyn till kreditbetygsmigrationer, säsongskomponenten i affärscykeln och tidsserieanalys. En analys utfördes mellan två olika kreditportföljer för att tolka resultaten. Resultaten visade att graden av PIT-ness var lägre i en kreditportfölj med få fallissemang jämfört med en testportfölj som uppvisade en större mängd kreditbetygsmigrationer med en större magnitud. Vikten av att beakta relevanta makroekonomiska variabler för att representera affärscykeln nämndes bland de viktigaste faktorerna att beakta för att få tillförlitliga resultat givet det föreslagna måttet.

Mole salamanders (Ambystoma) and woodfrogs (Lithobates sylvaticus) are abundant in New England and depend on ephemeral wetlands for breeding. Their aquatic habitats have been well studied and are protected by several local and regional regulations. State endangered species laws also protect mabled salamanders (A. opacum), Jefferson salamanders (A. jeffersonianum), and blue-spotted salamanders (A. laterale). However, these amphbibians spend most of their adult lives in terrestrial habitats that remain poorly protected and elusive to researchers. In chapter 1, I developed a novel technique using passive integrated transponders for tracking small animals. I used this technique to track marbled salamanders walking up to 200 m from their breeding pond during post-breeding migrations. In Chapter 2, I examined the importance of multiple habitat variables for predicting the distributions of woodfrogs and spotted salamanders at 455 ponds in western Massachusetts. Based on a variable-comparison technique I developed, the best predictor for either species of amphibian was the amount of forest in the surrounding vii landscape. Both species were found more frequently in upland forests where the ponds are least protected by state and federal wetland regulations. In chapter 3, I used my data from chapter 2 and three other similar data sets to conduct an analysis of spatial scale and to parameterize a recently published resistant kernel model. The complex model parameterized by an expert panel did significantly worse than the null model. The distributions of both amphibians were best predicted by measuring the landscape at very large scales (over 1000 m). The most effective scales for conservation may be largest for organisms of intermediate dispersal capability. In chapter 4, I explored the evolution and genetics of the Jefferson/blue-spotted/unisexual salamander complex. I framed research into the fascinating unisexual reproductive system with a model that relates nuclear genome replacement, positive selection on hybrids, and biogeography of the species complex. I parameterized this model using genetic data taken from salamanders spanning Massachusetts and an individual-based breeding simulation. If paternal genomes are transmitted to offspring with the frequencies reported from laboratory experiments, then my model suggests that there must be strong selection favoring unisexuals with hybrid nuclei.

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