O presente trabalho investiga o comportamento da chapa de latão C268, com 0,50 mm de espessura, quando exposto ao processo de Estampagem Incremental de Chapas de Metal (Incremental Sheet Metal Forming -ISMF). Especificamente para a pesquisa, foram utilizadas as modalidades de Estampagem Incremental com Ponto Simples (Single Point Incremental Forming- SPIF) e Estampagem Incremental de Múltiplos Passes (Multi Pass Single Point Incremental Forming- MSPIF). Os experimentos foram baseados em uma geometria de tronco de pirâmide de base quadrada com 100 mm de lado e 45 mm de profundidade. Para as estratégias de estampagem foi atribuído, a estampagem helicoidal. Como resultado principal, foi verificado o ângulo de parede máximo atingido por cada processo de estampagem incremental. Adicionalmente, ensaios de tração, análise de deformações e de rugosidade da chapa de latão foram realizados. Todos os seus resultados estão detalhados na investigação. Para os parâmetros adotados nestes experimentos, o ângulo de parede obtido por SPIF foi maior do que pelo estudo proposto por MSPIF. / The present study investigates the performance of the brass plate C-268 with 0.50 mm thickness, when exposed to Incremental Sheet Metal Forming (ISMF). Specifically for research, it was used the modalities Single Point Incremental Forming (SPIF) and Multi Pass Single Point Incremental Forming (MSPIF). The experiments were based on a truncated pyramid geometry with square base 100 mm side and 45 mm depth. For forming strategies has been assigned, the helical forming. As the main outcome, it was found the maximum wall angle achieved by each process of incremental printing. In addition, tensile tests, analysis of deformation and roughness of the brass sheet were performed. All results are detailed in the investigation. For the parameters used in these experiments, the wall angle obtained by SPIF is greater than the study proposed by MSPIF.

Numerous media analyses claim that supra-regional multi-resort season passes (mega passes) are negatively impacting skiing, snowboarding, and winter-sport communities. In particular, media claims that ski areas on these season passes are charging higher single-day lift ticket prices to nudge people to buy their season pass products. To test this claim, I use a hedonic pricing model to estimate the impact of season passes on adult single-day lift ticket prices. By applying OLS regressions to a dataset of 302 US ski areas for the winter of 2018-19, I find that the ski areas on the leading season passes (Ikon and Epic Pass) charge price premiums for their adult single-day lift tickets. However, the magnitude of the price premiums is much smaller after controlling for ski area characteristics and regional fixed effects.

This dissertation consists of essays that study exchange rate pass-through, China’s de facto exchange rate regime, and China’s capital controls. The first essay studies exchange rate pass-through (ERPT) by using a set of data from ten countries including four advanced economies and six Asian emerging markets. The price indices used in this essay include consumer price, producer price, import price and export price indices. While most literature only include the import price index, this essay also puts emphasis on the export price index. It investigates the asymmetry in the ERPT between depreciation and appreciation of domestic currency by using a non-linear OLS model; meanwhile, the short-run and long-run effects of ERPT are also compared with each other. It also detects possible structural change in the ERPT and finds most structural change points are around the Great Recession and Asia financial crisis. Finally, a VAR model is developed to detect the impulse responses of prices to exchange rate shock. The second essay is about China’s exchange rate regime. It has changed a lot since the 2005 reform. It is interesting and important to investigate China’s de facto exchange rate regime with the most recent data. This essay follows Frankel and Wei’s (2008) method, by applying both the basic model and new model with the exchange market pressure (EMP) variable to currency basket for the Chinese yuan exchange rate. I select the US dollar, the Euro, the British pound, the Japanese yen, the Canadian dollar, the Australian dollar and the Russian ruble as component currencies of the basket, based on free floaters, GDP and trade volume. I also add results from a VAR model, considering the endogeneity issue, and the results are consistent with those of OLS. I find the weight of the US dollar declines dramatically and the variation of the Chinese yuan becomes much larger after 2015. This implies that China has been transferring its exchange rate regime from dollar pegged to free floating. The third essay investigates the effectiveness of China’s capital controls. In recent years, after 2014, China’s foreign reserves declined dramatically, from 4 trillion US dollars to 3 trillion US dollars. There was a huge amount of capital outflows from China during 2015 to 2016. This phenomenon lets us reconsider the question: Are China’s capital controls still effective? I will use five methods to measure the effectiveness of China’s capital controls, including de jure indicators, saving-investment correlation test, covered interest rate parity, real interest rate differentials and Edwards-Kahn model. The de jure indicators I use are from Fernández et al. (2016) and Chinn and Ito (2008). I compare China with the US, the UK and Japan in the saving-investment correlation test, and with the Eurozone and Japan in covered interest rate parity, real interest rate differentials and Edwards-Kahn model. Various results indicate that China’s capital controls are still effective.

Thesis (M.Dev.) --University of Limpopo, 2012 / This study explores leadership in schools and its impact in grade twelve results productive school culture, and focuses on school leadership at selected schools in the Sekgosese West Circuit at Capricorn District in the Limpopo Province. Leadership plays a vital role in the functioning of any organisation, be it in business or in education, and the concept of leadership has become more prominent over the last decade. In order to develop a better understanding of leadership, a literature review is conducted. This review highlights the differences between leadership and management, and explores different leadership styles. This study finds that leadership challenges pose a serious threat to the attainment of good results in grade twelve (12) in Sekgosese West Circuit. These challenges emanate from a variety of factors such as lack of discipline, dysfunctional School Management Team, Involvement of parents, culture of teaching and learning, curriculum and possible solutions to leadership. Further, administering schools in a democratic fashion still pose tremendous challenges to the school leadership as a whole. It seems as if some schools which are part of this investigation still struggle to adjust to a democratic dispensation. This research therefore concludes that school leaders need to ensure that they are both good managers and effective leaders. They must also ensure that the culture at their schools is conducive for teaching and learning.

Both economists and policy makers are interested in understanding the welfare effect of economic policies, especially in small open economies such as Turkey and Iran. This knowledge is crucial for priority setting in any informed policy discussion. This dissertation aims to study the impoverishing effect of high levels of out-of-pocket (OOP) payments in the health sector, referred to as catastrophic health expenditure (CHE), and investigates the impact of exchange rate pass-through (ERPT) on both the microeconomic and macroeconomic indicators of a country. For millions of people worldwide, health payments present a huge financial risk. A high rate of OOP health care payments can lead to CHE, which can force households to cut down their consumption, minimize access to their needs, or face poverty. This makes the design of financial risk protection necessary for governments in order to secure people against the financial hardship at the time of incurring CHE. This thesis comprises three essays. The first investigates financial risk protection indicators related to OOP health care payments through CHE mean positive overshoot and incidence and depth of impoverishment. This research observes that in the absence of universal health care insurance in Iran, together with a high share of OOP spending for health care (more than 52%), the Iranian households facing CHE will eventually face poverty. In the second essay, using a difference-in-differences propensity score matching approach, I seek to analyze the degree to which Iranian universal health care insurance protects households from high rates of OOP health expenditure. In this study, I evaluate the effect of the universal health insurance program on Iranian CHE. The results show that the program was successful in decreasing the rate of OOP health expenditures and CHE in Iran during the sample period. The third essay estimates the ERPT using product-level daily data on wholesale prices of imported agricultural products, where the identification is possible by using daily data on the domestic inflation rate. The results of standard empirical analyses are in line with existing studies that employ lower frequencies of data by showing evidence for incomplete daily ERPT of about 5 percent.

The thesis treats roll pass design in wire rod rolling of stainless steel for sequences and series built up by two-symmetrical grooves. It is focused on predicting rolling flexibility, also called working range, as well as product quality. For analysing the flexibility a computer program has been developed. The minimum and maximum roll gap and corresponding bar areas for series of grooves including "oval", "round", "false round", "square" and "diamond" shapes are calculated. Six pass designs used in Swedish mills are analysed. Full-scale rolling is compared with laboratory experiments for the square-oval and false round (round)-oval series. The false round-oval series offers the largest working range and that the flexibility is smaller for pass sequences designed for high reductions. The false round-oval series are also acknowledged as a series for high quality steels and are usually better than the square-oval series having a tendency for defect formation. The thesis also includes high-speed rolling of wire rod in blocks. Here interstand tensions are utilised in order to keep the process stable. For obtaining the required dimensional tolerances of the product they are kept as low as possible. However interstand tensions could be used in order to increase the working range and move the product range towards smaller wire cross sections. For analysing this possibility, a narrow spread technology is utilised. At present time a practical problem is referred to the fixed gearings in the common blocks, which require a certain and given level of interstand tensions and corresponding reductions. This problem can however be solved by means of new block design and modern process control technology. Roll stands can be separately driven and controlled at very high speeds. Thus the eight stand blocks can be subdivided into four plus four passes blocks with a cooling line between enabling also higher productivity without violating the product quality because defect formations caused by a too high rolling temperature. The true working range of a series for a specific steel grade is however not only dependent on the possible spectrum of wire dimensions that can be obtained but might also depend on its ability to decrease or eliminate defects such as surface cracks. Thus, the behaviour of artificial V-shaped cracks in the longitudinal direction has been investigated and compared for the square-oval and false round (round)-oval series mentioned above. In agreement with other research works it was established that efficient rolling conditions for reducing the cracks are obtained when the cracks open up at the same time as their depth is reduced. If the V-shaped crack is closed by contact between its oxidized side surfaces the rolling schedule is not optimal for getting a high quality product. A deeper understanding of the experimental results was obtained by means of an FE-analysis

This study investigates the interest rate pass through from the money market rate to the lending rate by utilizing monthly data of fifteen countries, grouped as high income, upper middle income and lower middle income, over the period 1999:01-2011:09. Taking the linear cointegration test of Engle-Granger as benchmark, we employ threshold cointegration tests of Enders and Siklos (2001) in order to account for the possible nonlinearities in the pass-through process. Empirical results reveal that the pass through process is complete in three countries / Republic of Korea, Latvia and Malaysia and the adjustment of the lending rate is symmetric in two countries / Armenia and Republic of Korea. Moreover, it is observed that the adjustment of the lending rate is upward sticky in six countries / Bolivia, Philippines, Malaysia, Dominican Republic, Thailand and Croatia, whereas it is downward sticky in seven countries / Ukraine, Sri Lanka, Latvia, Peru, Kuwait, Hong Kong and Czech Republic. Furthermore, our estimation results suggest that heterogeneities in the pass-through mechanism across countries can be mainly explained by income level, inflation, market power, financial sector development and market volatility.

The objective of this thesis is the development of algorithms for the simulation of the light transport in general environments to render high quality still images. To this end, first we have analyzed the existing methods able to render participating media, more concretely those that account for multiple scattering within the media. Next, we have devised a couple of two pass methods for the computation of those images. For the first step we have proposed algorithms to cope with the scenes we want to deal with. The second step uses the coarse solution of the first step to obtain the final rendered image.The structure of the dissertation is briefly presented below.In the first chapter the motivation of the thesis and its objectives are discussed. It also summarizes the contributions of the thesis and its organization.In the second chapter the principles of global illumination for general environments are reviewed, with the most important equations---the rendering equation and the transport equation---whose solution constitutes the global illumination problem. In order to solve the global illumination problem, a certain number of multi-pass methods exist. Their objective is to be able to skip restrictions on the number of types of light paths that could be dealt with a single technique, or increase efficiency and/or accuracy. We have opted to follow this philosophy, and a pair of two pass methods have been developed for general environments.The third chapter includes the study of the methods that perform the single scattering approximation, and also the study of the ones that take into account multiple scattering.The fourth chapter is devoted to our first pass method, which computes a rough estimate of the global illumination. Knowing the benefits of hierarchical approaches, two concrete algorithms based on hierarchies have been extended to be more generic: Hierarchical Radiosity with Clustering and Hierarchical Monte Carlo Radiosity.Our second pass is considered in the next chapter. Using the coarse solution obtained by the first pass, our second pass computes a high quality solution from a given viewpoint. Radiances and source radiances are estimated using Monte Carlo processes in the context of path tracing acceleration and also for final gather. Probability density functions (PDFs) are created at ray intersection points. For such a task, we initially used constant basis functions for the directional domain. After realizing of their limitations we proposed the Link Probabilities (LPs), which are objects with adaptive PDFs in the links-space.In order to take advantage of the effort invested for the construction of the LPs, we have devised two closely related progressive sampling strategies. In the second pass, instead of sampling each pixel individually, only a subset of samples is progressively estimated across the image plane. Our algorithms are inspired by the work of Michael D. McCool on anisotropic diffusion using conductance maps.The final chapter presents the conclusions of the thesis. Also possible lines of further research are suggested. / El objetivo de esta tesis es el desarrollo de algoritmos para la simulación del transporte de la luz en los entornos genéricos para generar imágenes de la alta calidad. Con este fin, primero hemos analizado los métodos existentes capaces de visualizar medios participativos, más concretamente los que tienen en cuenta la dispersión múltiple en los medios. Después, hemos ideado un par de métodos de dos pasos para el cómputo de esas imágenes. Para el primer paso hemos propuesto algoritmos que hacen frente a las escenas que deseamos tratar. El segundo paso utiliza la solución aproximada del primer paso para obtener la imagen final. La estructura de la disertación se presenta brevemente en lo que sigue.En el primer capítulo se discuten la motivación de la tesis y sus objetivos. También se resumen las contribuciones de la tesis y su organización. En el segundo capítulo se repasan los principios de la iluminación global para los ambientes genéricos, con las ecuaciones-más importantes (la ecuación de rendering y la ecuación de transporte) cuya solución constituye el problema global de iluminación. Para solucionar el problema global de iluminación, cierto número de métodos de múltiples pasos existen. Su objetivo es poder eliminar restricciones en el número de tipos de caminos de luz que se podrían tratar con una sola técnica, o aumentar su eficacia y/o exactitud. Hemos optado seguir esta filosofía, desarrollando un par de métodos de dos pasos para entornos genéricos.El tercer capítulo incluye el estudio de los métodos que utilizan la aproximación de dispersión simple, y también el estudio de los que consideran la dispersión múltiple.El cuarto capítulo está dedicado a nuestro método de primer paso, que computa un cálculo aproximado de la iluminación global. Conociendo las ventajas de los métodos jerárquicos, dos algoritmos concretos basados en jerarquías se han ampliado para ser más genéricos: radiosidad jerárquica con clustering y radiosidad jerárquica usando Monte Carlo. Nuestro segundo paso se considera en el capítulo siguiente. Usando la solución aproximada obtenida por el primer paso, el segundo paso computa una solución de la alta calidad para un punto de vista dado. Se estiman las radiancias usando procesos de Monte Carlo en el contexto de la aceleración de trazadores de rayos y también para final gather. Las funciones de densidad de probabilidad (PDFs) se crean en los puntos de interacción de los rayos. Para tal tarea, utilizamos inicialmente funciones constantes como base para el dominio direccional. Después de comprender sus limitaciones, propusimos establecer probabilidades directamente sobre los enlaces (link probabilities, o LPs), usando objetos con PDFs adaptativos en el espacio de los enlaces.Para aprovechar el esfuerzo invertido en la construcción de los LPs, hemos ideado dos estrategias de muestreo progresivas. En el segundo paso, en vez de muestrear cada pixel individualmente, solamente se estima progresivamente un subconjunto de muestras a través del plano de imagen. Nuestros algoritmos han sido inspirados en el trabajo de Michael D. McCool en la difusión anisotrópica usando mapas de conductancia.El capítulo final presenta las conclusiones de la tesis, y también sugiere las líneas posibles de investigación futura.

Bakgrund: Monaurala lågredundanta taltester används, tillsammans med andra tester i testbatterier, för att undersöka centrala auditiva funktioner. Testgrupper som ingår i monaurala lågredundanta taltester är: lågpassfiltrerade taltester, tal-i-brus tester och tidskomprimerade taltester. Syfte: Syftet var att ta reda på vilka monaurala lågredundanta taltester som finns och vilka resultat man kan få på dessa. Metod: Litteraturstudie där experimentella studier har använts. Resultat: De monaurala lågredundanta taltester som har använts i de studerade artiklarna är filtrerat tal, meningar-i-brus, ord-i-brus, taluppfattning-i-brus, tal-i-brus, SPIN, R-SPIN, SSI/MCI, SSI/ICM, SIN, tidskomprimerade ord med olika kompressionsgrader, hackat tal, The Compressed Sentence Test och SCAN-A, SCAN-C med undertesterna Auditory Figure Ground och filtrerade ord. Försökspersoner med hörselnedsättning får signifikant sämre resultat än normalhörande på många av testerna. Barn får sämre resultat på flera av testerna jämfört med vuxna. Slutsatser: Det finns många olika monaurala lågredundanta taltester. De valda artiklarna tar upp fler monaurala lågredundanta taltester än vad som nämns i använd referenslitteratur.

Binary measurement systems (BMS) are widely used in both manufacturing industry and medicine. In industry, a BMS is often used to measure various characteristics of parts and then classify them as pass or fail, according to some quality standards. Good measurement systems are essential both for problem solving (i.e., reducing the rate of defectives) and to protect customers from receiving defective products. As a result, it is desirable to assess the performance of the BMS as well as to separate the effects of the measurement system and the production process on the observed classifications. In medicine, BMSs are known as diagnostic or screening tests, and are used to detect a target condition in subjects, thus classifying them as positive or negative. Assessing the performance of a medical test is essential in quantifying the costs due to misclassification of patients, and in the future prevention of these errors. In both industry and medicine, the most commonly used characteristics to quantify the performance a BMS are the two misclassification rates, defined as the chance of passing a nonconforming (non-diseased) unit, called the consumer's risk (false positive), and the chance of failing a conforming (diseased) unit, called the producer's risk (false negative). In most assessment studies, it is also of interest to estimate the conforming (prevalence) rate, i.e. probability that a randomly selected unit is conforming (diseased). There are two main approaches for assessing the performance of a BMS. Both approaches involve measuring a number of units one or more times with the BMS. The first one, called the "gold standard" approach, requires the use of a gold-standard measurement system that can determine the state of units with no classification errors. When a gold standard does not exist, is too expensive or time-consuming, another option is to repeatedly measure units with the BMS, and then use a latent class approach to estimate the parameters of interest. In industry, for both approaches, the standard sampling plan involves randomly selecting parts from the population of manufactured parts. In this thesis, we focus on a specific context commonly found in the manufacturing industry. First, the BMS under study is nondestructive. Second, the BMS is used for 100% inspection or any kind of systematic inspection of the production yield. In this context, we are likely to have available a large number of previously passed and failed parts. Furthermore, the inspection system typically tracks the number of parts passed and failed; that is, we often have baseline data about the current pass rate, separate from the assessment study. Finally, we assume that during the time of the evaluation, the process is under statistical control and the BMS is stable. Our main goal is to investigate the effect of using sampling plans that involve random selection of parts from the available populations of previously passed and failed parts, i.e. conditional selection, on the estimation procedure and the main characteristics of the estimators. Also, we demonstrate the value of combining the additional information provided by the baseline data with those collected in the assessment study, in improving the overall estimation procedure. We also examine how the availability of baseline data and using a conditional selection sampling plan affect recommendations on the design of the assessment study. In Chapter 2, we give a summary of the existing estimation methods and sampling plans for a BMS assessment study in both industrial and medical settings, that are relevant in our context. In Chapters 3 and 4, we investigate the assessment of a BMS in the case where we assume that the misclassification rates are common for all conforming/nonconforming parts and that repeated measurements on the same part are independent, conditional on the true state of the part, i.e. conditional independence. We call models using these assumptions fixed-effects models. In Chapter 3, we look at the case where a gold standard is available, whereas in Chapter 4, we investigate the "no gold standard" case. In both cases, we show that using a conditional selection plan, along with the baseline information, substantially improves the accuracy and precision of the estimators, compared to the standard sampling plan. In Chapters 5 and 6, we investigate the case where we allow for possible variation in the misclassification rates within conforming and nonconforming parts, by proposing some new random-effects models. These models relax the fixed-effects model assumptions regarding constant misclassification rates and conditional independence. As in the previous chapters, we focus on investigating the effect of using conditional selection and baseline information on the properties of the estimators, and give study design recommendations based on our findings. In Chapter 7, we discuss other potential applications of the conditional selection plan, where the study data are augmented with the baseline information on the pass rate, especially in the context where there are multiple BMSs under investigation.