TESIs POSTÍTULO DE ECONOMÍA Y FINANZAS PARA ABOGADOS / La ley 20.780 introdujo un nuevo impuesto a las fuentes móviles de contaminación, que grava la compraventa de vehículos nuevos. Sí bien se declaró que se trataba de un impuesto verde, es decir, que fue establecido para desincentivar las conductas contaminantes, lo cierto es que no lo ha logrado efectivamente y solo ha generado un aumento en la recaudación fiscal. Se analizará el concepto de impuesto verde en abstracto, la historia fidedigna de la modificación legal y los datos del mercado automotor. Law 20,780 introduced a new tax on movable sources of pollution, which levies the purchase of new vehicles. Despite having being declared as a green tax, that is, having being established to discourage polluting behaviors, this has not been successfully achieved, and has only increase the tax collection. It will be further analyzed the abstract concept of green tax, the history of the legal amendment and data from the vehicle market. / Law 20,780 introduced a new tax on movable sources of pollution, which levies the purchase of new vehicles. Despite having being declared as a green tax, that is, having being established to discourage polluting behaviors, this has not been successfully achieved, and has only increase the tax collection. It will be further analyzed the abstract concept of green tax, the history of the legal amendment and data from the vehicle market.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第22279号 / 理博第4593号 / 新制||理||1659(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 本川 雅治, 准教授 中野 隆文, 教授 曽田 貞滋 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

Wurtzite III-nitride semiconductor materials have many technically important applications in optical and electronic devices. As GaN-based visible light-emitting diodes (LEDs) and lasers starts to mature, interest in developing UV devices starts to rise. The search for materials with larger bandgaps and high refractive index contrast in the UV range has inspired multiple studies of BN-based materials and their alloys with traditional III-nitrides. Additionally, alloying III-nitrides with boron can reduce their lattice parameters giving a new option for strain engineering and lattice matching. In this work I investigate the refractive indices of BAlN and BGaN over the entire compositional range using hybrid density functional theory (DFT). An interesting non-linear trend of the refractive index curves appears as boron content is increased in the BAlN and BGaN alloys. The results of this calculation were interpolated and plotted in three dimensions for better visualization. This interpolation gives a 3D dataset that can be used in designing a myriad of devices at all binary and ternary alloy compositions in the BAlGaN system. The interpolated surface was used to find an optimum design for a strain-free, high reflection coefficient and high bandwidth DBR. The performance of this DBR was quantitatively evaluated using finite element simulations. I found that the maximum DBR reflectivity with widest bandwidth for our materials occurs at a lattice parameter of 3.113 Å using the generated 3D dataset. I use the corresponding material pair to simulate a DBR at the wavelength 375 nm in the UVA range. A design with 25 pairs was found to have a peak reflectivity of 99.8%. This design has a predicted bandwidth of 26 nm measured at 90% peak performance. The high reflectivity and wide bandwidth of this lattice-matched design are optimal for UVA VCSEL applications. I have assisted in exploring different metalorganic chemical vapor deposition (MOCVD) techniques, continuous growth and pulsed-flow modulation, to grow and characterize BAlN alloys. Samples grown using continuous flow show better optical quality and are characterized using spectroscopic ellipsometry. The refractive index of samples obtained experimentally is significantly below the predicted value using DFT.

Wheat consumption has become more widespread and is increasing in South Africa especially in the urban areas. The wheat industry contributes four billion rands to the gross value of agriculture and is a source of employment to approximately 28 000 people. Wheat yield forecasting is crucial in planning for imports and exports depending on the expected yields and wheat health monitoring is important in minimizing crop losses. However, current crop surveying techniques used in South Africa rely on manual field surveys and aerial surveys, which are costly and not timely (after harvest). This research focuses on wheat health monitoring and wheat yield prediction using remote sensing, which is a cost effective, reliable and time saving alternative to manual surveys. Hence, the research objectives were: (i) to identify remotely sensed spectral indices that comprehensively describe wheat health status. (ii) Develop an Normalized Difference Vegetation Index (NDVI) based wheat yield forecasting model and (iii) to evaluate the impact of selected agrometeorological parameters on the NDVI based forecasting model. Landsat 8 images were used for determining spectral indices suitable for wheat health monitoring by relating the spectral indices to the land surface temperature. Results show that the Normalized Difference Water Index (R2 between 0.65 and 0.89) and NDVI (R2 between 0.36 and 0.62) were the most suitable indices for wheat health status monitoring. Whereas, the Normalized Difference Moisture Index (R2 between 0.53 and 0.79) and the Green Normalized Difference Vegetation Index (R2 between 0.28 and 0.41) were found to be less suitable for wheat health monitoring. Moderate Resolution Spectroradiometer (MODIS) derived NDVI for fourteen years was used to build and test a wheat yield forecasting model. The model was significant with an R2 value of 0.73, a p-value of 0.00161 and an RMSE of 0.41 tons ha-1. The study established that the period 30 days before harvest during the anthesis growth stage, is the best period to use the linear regression model for wheat yield forecasting. Satellite derived agrometeorological parameters such as: soil moisture, evapotranspiration and land surface temperature were added to the NDVI based model to form a multi-linear regression model. The addition of these parameters to the NDVI model improved it from an R2 of 0.73 to an R2 of 0.82. Through the use of a correlation matrix, the NDVI (r=0.88) and evapotranspiration (r=0.58) were highly correlated to wheat yield as compared to soil moisture (r=0.27) and land surface temperature (r=-0.02). This research provided evidence that remote sensing can be used at acceptable levels of accuracy for wheat monitoring and wheat yield predictions compared to manual field surveys which are costly and time consuming. / Dissertation (MSc)--University of Pretoria, 2017. / Agricultural Research Council / National Research Foundation / Spatial Business IQ / GeoTerra Images / University of Pretoria / Geography, Geoinformatics and Meteorology / MSc / Unrestricted

PhDRDV / Institute for Rural Development / In South Africa, various government and private sector-led initiatives have been directed towards promoting youth involvement in small retail businesses. This was designed to counter the high unemployment and poverty rates among youth. However, high failure rates of the initiatives consistently frustrate these noble efforts. Even though this is the case, neither attributes of youth-run small retail business resilience nor the factors that predispose them to the high failure rates are well-known. This situation demands taking urgent action to foster resilience in the youth-run small retail business sector. Thus, the current study focused on identifying the major threats and strengths to business and determining a set of objective criteria and indices for use in measuring resilience. Potential resilience strategies were also sought. The study was conducted in Vhembe District of Limpopo Province in South Africa. An explorative mixed research approach was employed. Participants were selected using both snowball and cluster sampling procedures. Data were collected using semi-structured interview guides and questionnaires. Qualitative data were analysed using Atlas ti version 8 software techniques such as network diagrams and code primary document tables. For each objective, in-depth results were obtained, further interrogated in a survey and analysed using the Statistical Package for Social Sciences software (IBM SPSS; version 25) in the subsequent phase. The main statistical techniques utilised were Principal Component Analysis (PCA) and Kruskal-Wallis tests. Significance was determined at P< 0.5. Results from PCA test reviewed three major threats to small retail business resilience that included poor infrastructure (28.54 %), financial infrastructure (20.97 %) and competition (14.94 %). The three factor structure accounted for a total variance of 64.46 %. Poor infrastructure and financial inadequacy threats did not vary with distance from the urban area (P > 0.05) while competition significantly varied with distance from the urban area (P< 0.05). With regard to strengths, PCA analysis produced a four factor structure that explained a total variance of 54.59 %. The four major strengths included marketing ability (16.97 %), good customer care (14.42 %), business knowledge (12.08 %) and commitment (11.13 %). A six dimension criteria for measuring small retail business resilience was established using PCA. The six dimensions encompassed security measures (18.01 %), outsourcing abilities (13. 70 %), marketing strategies (10.07), risk management (8.54 %), financial management (8.43 %) and innovation (7.89 %). The six factor structure explained a total variance of 66.67 %. These resilience pillars were related to threat detection, prevention and adaptation business mechanisms. Four resilience dimensions (security measures, marketing abilities, risk management and innovation) were similar across distance variations from the urban area (P> 0.05). However, significant differences between urban and rural areas were observed in two variables, that is, joining business alliances (P=0.012) linked to outsourcing abilities and keeping money away from the business premise (P=0.034) associated with financial management. Resilience indices were further developed utilising the six building blocks of the criteria. The indices for measuring small retail business resilience were expressed in the formula: R1= ƒ (SM1, OA1, MS1, RM1, FM1, I1, S1) + e where SM=Security Measures; OA= Outsourcing Abilities; MS= Marketing Strategies; OM=Risk Management; FM= Financial Management; I= Innovation; S= Subjective resilience dimensions and 1= particular time; e= error. The assumption underpinning these indices was that, small retail business resilience is not observable and thus it can be measured through assessing each dimension separately at a particular time. The outcomes reflected that, measuring youth-owned small retail businesses resilience encompasses a clear understanding of area specific threats and the subsequent customised performance measures. Resilience dimensions may change with time due to socio-economic changes, government policies and local conditions. As such, it is crucial to constantly assess youth small retail businesses in order to determine their current status and changes in resilience components. Current strategies and potential interventions for promoting small business resilience were also reviewed. Small retailers were currently utilising strategies such as business collaboration, specialisation and stock diversification. To, address the weaknesses associated with presently utilised strategies, potential interventions that encompassed financial support, provision of cheap stands, need for financial assistance and provision of business training and infrastructure upgrades were proposed. The present study provided a criteria and resilience indices that can be used by policy implementers, development agencies and funders to determine resilience drivers, monitor changes in resilience attributes over time and identify necessary interventions in the small retail sector. This assists decision makers to make pre-informed decisions before providing support to youth small retailers. The use of participatory research methods in the present study helped to ground the work in the youth small retail sector and thus, contributing to community engagement practices. The use of mixed study approaches has been consistently recommended in studies related to resilience measurement methods. As a result, the mixed research methods utilised in the present study provides directions for future replication in studies aimed at developing approaches for measuring resilience in the small business sector. Lastly, the simplicity of the criteria and indices make it easier for small retail business owners and other practitioners to use in future. / NRF

Actively-managed funds have recently come under fire as it has been determined that they consistently underperform passive funds. Benchmarking, and the constraints placed on actively-managed funds, are standard practices within the industry, but research suggests that these constraints negatively affect fund performance. This research paper explores the effectiveness of actively-managed funds in relation to their benchmark indices, in terms of tracking errors and weighting constraints. This is done by qualifying the effect of these constraints on the performance of hypothetically constructed portfolios in relation to the FTSE / JSE Top 40 Index. The results are presented graphically and show that tracking error limits did, as expected, limit the possible upside returns of these funds. It was found however, that the tracking error constraints had a much greater effect on limiting downside risk than they had on limiting upside effects. Weighting limitations did not have a single universal effect on the simulated portfolios’ performance but affect performance in conjunction with tracking error limits. It was concluded that for the hypothetically constructed portfolios for the period studied, constraints did not affect the possible upside return to such a magnitude that the constraints themselves could account for the underperformance of actively managed funds and they had an overall positive effect on performance. / Mini Dissertation (MBA)--University of Pretoria, 2018. / Gordon Institute of Business Science (GIBS) / MBA / Unrestricted

The purpose of this study is to investigate how indexical storytelling in a 3D scene could affect the players understanding of narrative and how they navigate the scene. The background of the study presents what indexical storytelling is and goes briefly into color interpretation.To answer how indexical storytelling affects players a 3D scene was made, containing indexical objects which the 10 participants could go through and explore in semi-structured qualitative interviews. This was to see if the participants understood the narrative of the scene and the similarities or dissimilarities between people with experience in different game genres.The result showed a possible tendency in the participants understanding the narrative of the scene. But additional studies and participants are required to be able to come to any larger scale conclusion or generalizations. / <p>Det finns övrigt digitalt material (t.ex. film-, bild- eller ljudfiler) eller modeller/artefakter tillhörande examensarbetet som ska skickas till arkivet.</p>

The first comprehensive study of equatorial- to mid-latitude ionospheric electric fields (plasma drifts) is presented, using extensive incoherent scatter radar measurements from Jicamarca, Arecibo, and Millstone Hill, and F-region ion drift meter data from the polar orbiting DE-2 satellite. Seasonal and solar cycle dependent empirical quiet-time electric field models from equatorial to mid latitudes are developed, which improve and extend existing climatological models. The signatures of electric field perturbations during geomagnetically disturbed periods, associated with changes in the high-latitude currents and the characteristics of storm-time dynamo electric fields driven by enhanced energy deposition into the high-latitude ionosphere, are studied. Analytical empirical models that describe these perturbation drifts are presented. The study provided conclusive evidence for the two basic components of ionospheric disturbance electric fields. It is shown that magnetospheric dynamo electric fields can penetrate with significant amplitudes into the equatorial- to mid-latitude ionosphere, but only for periods up to 1 hour, consistent with results from the Rice Convection Model. The storm-time wind-driven electric fields are proportional to the high-latitude energy input, vary with local time and latitude, and have largest magnitudes during nighttime. These perturbations affect differently the zonal and meridional electric field components. It is shown that equatorial zonal electric fields (vertical drifts) can be disturbed up to 30 hours after large enhancements in the high-latitude currents. These perturbation electric fields are associated with enhanced high-latitude energy deposition taking place predominantly between about 1-12 hours earlier and found to be in good agreement with the Blanc-Richmond disturbance dynamo model. A second class of perturbations occurs around midnight and in the dawn-noon sector with delays of about 18-30 hours between the equatorial- and the high-latitude disturbances , and maximizes during locally quiet geomagnetic times. The latitudinal variation of the meridional disturbance electric fields (zonal drifts) is also presented. It is shown that these perturbation electric fields are predominantly downward/equatorward at all latitudes and due to both prompt penetration and disturbance dynamo electric fields. These results are also generally consistent with predictions from global convection and disturbance dynamo models.

Evolution of rocky coastlines is controlled by littoral, biological and fluvial processes. Resultant landforms are overprinted and/or new ones formed as a result of changes in sea level caused by glacioeustasy and/or local tectonics. On carbonate coasts, chemical erosion in the form of karstification takes on a dominant role. Type of karstification is an important factor in understanding carbonate coast evolution and landform development so it is critical to identify type of karstification. In this research, fractal indices were used to distinguish cave and thus karstification type. It was determined that fractal indices effectively differentiated cave types and the indices were used to distinguish cave types at study sites on Barbados, the ABC Islands (Aruba, Bonaire, Curaçao) and the Caribbean coast of the northeast Yucatan peninsula, Mexico. This research evaluated caves located in the phreatic, epiphreatic and vadose zones of the northeast coast of Quintana Roo, Mexico to determine the relationship between the caves and to coastal processes. Three distinct coastal landforms associated with caves on the study sites were evaluated to quantify and model the interplay of littoral, fluvial and karstic processes and cave and karst development. On Barbados, the combination of surface fluvial processes, and mixing-zone and fluvial-karstic dissolution, resulted in the formation of gullies. Some gullies contained caves in their bounding walls and/or served as points of recharge to fluvial caves. Bokas of the ABC islands are distinctive geomorphic structures that formed from the interplay of fluvial, littoral and mixing zone karstification. The morphology of the bokas was a function of dominant geomorphic process. The caletas of the Yucatan Caribbean were formed by karstification processes that also produced features with mixing-zone-like morphologies but with fluvio-karstic function. The results of this research expand the Carbonate Island Karst Model (CIKM), which explains eogenetic dissolutional processes and landforms on small carbonate islands, to one that includes carbonate islands of all sizes, and carbonate continental coasts.

Evaluating soil health using bioindicator organisms has been suggested as a method of analyzing the long-term sustainability of agricultural management practices. The main objective of this study was to determine the effects of vineyard management strategies on soil food web structure and function, using nematodes as bioindicators by calculating established nematode ecological indices. Three field trials were conducted in a commercial Pinot Noir vineyard in San Luis Obispo, California; the effects of (i) fertilizer type (organic and inorganic), (ii) weed management (herbicide and tillage), and (iii) cover crops (high or low water requirements) on nematode community structure, soil nutrient content, and crop quality and yield were analyzed. Overall, although nematode ecological indices indicated that all plots had disturbed soil food webs, the indices proved to be less useful for measuring subtle differences in soil management over the short-term than anticipated. They showed few differences treatments. In general, the most pronounced differences were seen by sample location (under the vine or in the tractor row) and sample date, rather than treatment. None of the evaluated strategies affected crop quality, although fertilizer had a slight effect on yield. However, several indices were correlated with soil chemical parameters, including pH, nitrogen, carbon, and, to a lesser extent, EC. These results indicate that while nematode indices can be useful for comparing the state of the soil food web under long-term soil conditions, they may not be a robust measure of how agricultural management practices change soil health over a single growing season.