In this dissertation three essays were presented. In the first two essays we measure the consumer welfare changes caused by U.S. meat price changes. In the third essay the dynamic structure of international gasoline prices using the time series methodology is investigated. In chapter II, we investigate the U.S. consumer behavior on meat consumption depending on a linear expenditure system (LES), and then we simulate the welfare effects of a set of price changes on the U.S. meat consumption. The simulation results show that the amount of consumer welfare change for each meat is not same across the meats under the same percentage change of price. The simulation results also show that when all the prices are doubled the total amount of CV reaches almost the same amount of current total quarterly expenditures for the three meats. In chapter III, we apply the compensating variation (CV) approach for the measurement of consumer welfare losses associated with beef price changes. We applied the long-run cointegrating relationship in vector error correction model (VECM) to estimate the Marshallian demand function. Apparently, the use of long-run cointegration in VECM in deriving the direct Marshallian demand function to measure the consumer welfare change is the first attempt in the literature. This is one of the contributions of the study. The simulation results show that the amount of consumer welfare change for beef is compatible with the one derived from LES methodology. In chapter IV, an empirical framework to summarize the interdependence of four international gasoline markets (New York, U.S. Gulf Coast, Rotterdam and Singapore) is presented. For that purpose, we employ a structural VECM and directed acyclic graphs (DAGs). To solve the identification problem in structural VECM, we apply DAGs derived from contemporaneous VECM innovations. The impulse response functions show that the time period in which a shock in a market affects the other market is very short. Forecast error variance decompositions (FEVD) shows that in all markets, except the U.S. Gulf Coast market, current and past shocks in their own market explained the most of the volatility in their own market in the Short-run.

This thesis compares two datasets, the Science and Engineering Indicators 2006 (SEI) and the 1993 National Survey of College Graduates (NSCG), and looks at the impact of sex on full-time annual salary while controlling for different variables. The SEI provides a study based on data from 1999 about the sex effects on salary, adds controls, and records the changes in the effect of sex on salary. The SEI study finds after adding controls for worker heterogeneity and compensating wage differentials, women with bachelor's degrees earn 11.0% less, women with master's degrees earn 8.0% less, and women with doctoral degrees earn 8.4% less than their male counterparts. My analysis of the NSCG finds after adding controls, women with bachelor's degrees earn 18.5% less, women with master?s degrees earn 18.7% less, and women with doctoral degrees earn 15.3% less than their male counterparts. Additionally, in the NSCG and the SEI the field of degree impacted the sex effects the most for bachelor's and master's degree holders. This research is useful to study the difference between these datasets from different time periods. Specifically, the difference in the sex wage gap and in the changing importance of certain variables affecting the sex wage gap.

Universal quantum computation requires precision control of the dynamics of qubits. Frequently accurate quantum control is impeded by systematic drifts and other errors. Compensating composite pulse sequences are a resource efficient technique for quantum error reduction. This work describes compensating sequences for ion-trap quantum computers. We introduce a Lie-algebraic framework which unifies all known fully-compensating sequences and admits a novel geometric interpretation where sequences are treated as vector paths on a dynamical Lie algebra. Using these techniques, we construct new narrowband sequences with improved error correction and reduced time costs. We use these sequences to achieve laser addressing of single trapped 40Ca+ ions, even if neighboring ions experience significant field intensity. We also use broadband sequences to achieve robust control of 171Yb+ ions even with inhomogeneous microwave fields. Further, we generalize compensating sequences to correct certain multi-qubit interactions. We show that multi-qubit gates may be corrected to arbitrary accuracy if there exists either two non-commuting controls with correlated errors or one error-free control. A practical ion-trap quantum computer must be extendible to many trapped ions. One solution is to employ microfabricated surface-electrode traps, which are well-suited for scalable designs and integrated systems. We describe two novel surface-electrode traps, one with on-chip microwave waveguides for hyperfine 171Yb+ qubit manipulations, and a second trap with an integrated high numerical aperture spherical micromirror for enhanced fluorescence collection.

The aim of this essay is to examine how students in 6-9 grade with reading and writing difficulties are treated and supported by teachers and staff at Ideskolan, a community school north of Stockholm. I have chosen to answer the following question: - How does Ideskolan cope with and support students with reading and writing difficulties This has in turn generated the following questions: - How is special education organized at Ideskolan? - Is a diagnose always needed in order to deploy extra support? The method I have employed is observation while participating, together with informal talks and interviews. I have visited Ideskolan twice, one week at the time. The material that the visits have generated is the foundation of the essay, supported by previous research in the field. The essay clarifies what right to special support students have according to law, regulations, curriculum and teaching plans and what they look like in reality at Ideskolan. This paper questions why schools focus on the individual student in these matters instead on the schools organisation and way of working. It might not automatically be the students’ difficulties with reading and writing that limits their continued learning, but rather the schools attitude towards students with special needs. Some ways of working might minimize the difficulties while some can increase them. If so, perhaps a change is in order? The essay also discusses the role of the special teacher – should she be supporting the students or her colleagues, or both. It also discusses if the teacher training should evolve to better suite the need to handle students with reading and writing difficulties. Even though Ideskolan recognizes the fact that two – three students in each class suffers with reading and writing difficulties the support to these students are inadequate. The school can excuse it self by saying that there is no “right way to go”, for each student with reading and writing difficulties are unique and there for require different support.

Este projeto de pesquisa foi desenvolvido visando quantificar possíveis distúrbios de vazão em emissores do tipo gotejador (irrigação localizada) submetidos à aplicação de cloro livre e acidificação em condições estática e dinâmica de fluxo de água no sistema. O experimento foi realizado no período de setembro de 2005 a junho de 2006, utilizando-se 14 modelos de gotejadores autocompensantes com suas respectivas linhas gotejadoras montadas em uma bancada de ensaios em estrutura metálica. Os tratamentos utilizados no experimento foram: a) aplicação dinâmica de 100 mg L-1 de cloro livre com pH na faixa de 5,5 a 6,0; b) aplicação estática de 100 mg L-1 de cloro livre com pH na faixa de 5,5 a 6,0; c) aplicação de ácido nítrico com pH na faixa de 2,0 a 3,0 durante ½ h (sistema pressurizado); d) aplicação de ácido nítrico com pH na faixa de 2,0 a 3,0 durante 12 h (sistema pressurizado). Foram realizadas curvas vazão versus pressão para cada tratamento em três diferentes temperaturas da água (15, 25 e 40° C). O delineamento experimental utilizado foi o inteiramente aleatorizado em esquema fatorial, com utilização dos testes ?F? para análise de variância e Tuckey, a 5% de significância, para comparação de médias e análise de regressão. Os resultados obtidos mostram que para o tratamento da água com 100 mg L-1 de cloro livre em condição dinâmica, ocorreu um decréscimo de 10 a 20% em média da vazão (L h-1) para alguns modelos de gotejadores mais sensíveis aos produtos químicos, sendo que o modelo I apresentou redução drástica de vazão na ordem de 100% em virtude do bloqueio total do labirinto do emissor, em decorrência do aumento de 112% do volume da membrana após 2688 h de aplicação contínua de cloro. Os tratamentos estáticos não apresentaram variações acentuadas de vazão média (L h-1), coeficiente de variação (%), uniformidade de distribuição (%), Vazão Relativa (%) e Grau de Entupimento (%). Verificou-se relação linear entre a vazão e a temperatura da água para os gotejadores novos, sendo que após a aplicação dos diferentes tratamentos, as curvas vazão versus pressão para cada modelo de gotejador sofreram influência tanto da pressão quanto da temperatura de maneira distinta. / This research project was developed to quantify possible flow rate variation in emitters (drip irrigation) submitted to the application of free chlorine and acidification under static and dynamics conditions of water flow. The experiment was accomplished in the period of September, 2005 to June, 2006, being analyzed 14 models of pressure compensating emitters set up in a metallic bench. The treatments used in the experiment were the following ones: a) dynamic application of 100 mg L-1 of free chlorine with pH 5,5 to 6,0; b) static application of 100 mg L-1 of free chlorine with pH 5,5 to 6,0; c) application of acid nitric with pH 2,0 to 3,0 during ½ h (pressurized system); d) application of acid nitric with pH 2,0 to 3,0 during 12 h (pressurized system). The operating pressures and emitter model combination were: 50, 100, 200, 300, 400 kPa for emitters A to N, in three different water temperatures (15, 25 and 40° C). The obtained values of flow rate were used to calculate the CUD, CV, relative flow rate, the percentage of drippers in each flow rate range, and the number of the drippers completely clogged. The statistical analysis of the treatments were accomplished by Tukey test at 5% probability. The obtained results show that for the treatment of the water with 100 mg L-1 of free chlorine in dynamic condition, a reduction from 10 to 20% of the flow rate (L h-1) occurred for some models more sensitive to chemical products. Model I presented drastic reduction of flow rate in the order of 100% by total blockade of the labyrinth of the emitter, due to the increase of 112% of the volume of the membrane after 2688 h of continuous application of 100 mg L-1 of chlorine free with pH 5,5 to 6,0. The static treatments didn\'t present accentuated variations of medium flow rate (L h-1), variation coefficient (%), distribution uniformity (%), relative flow rate (%) and degree of blockage (%). For pressure compensating emitters, where the discharge sensitivity to temperature is insignificant, after the application of the different treatments, the measured discharge/pressure relationship for each emitter model was sensitive to pressure as well to temperature.

The aim of this work is to find out why the structure of the market for sexual services changed in the years 1999 -- 2009 : why did the number of erotic clubs and the sex workers in clubs and on streets decrease and why did the number of sex workers in apartments increase? The change in nationality of composition of consumers and the development of internet are main factors of the changes. A high correlation proved to be between the number of sex workers and the number of tourists. Because of economic convergence tourists can buy less sexual services than in past whereas Czech can buy more. Other question is why earnings of sex workers are higher in comparison with wages of the women with the comparable education. The main factor is a social stigmatization.

Submitted by Lucienne Costa (lucienneferreira@ufcg.edu.br) on 2018-04-25T18:23:50Z No. of bitstreams: 1 GERÔNIMO BARBOSA ALEXANDRE – DISSERTAÇÃO (PPGEE) 2016.pdf: 6425501 bytes, checksum: 944e1e5c2f2c2cc350f12149a5877ed1 (MD5) / Made available in DSpace on 2018-04-25T18:23:50Z (GMT). No. of bitstreams: 1 GERÔNIMO BARBOSA ALEXANDRE – DISSERTAÇÃO (PPGEE) 2016.pdf: 6425501 bytes, checksum: 944e1e5c2f2c2cc350f12149a5877ed1 (MD5) Previous issue date: 2016-11-28 / Este trabalho foca na proposta e validação de estratégias de controle para regulação simultânea da tensão e frequência em micro redes isoladas, compensação de harmônicos de tensão no ponto comum de acoplamento (PCC) e a cooperação de potência reativa entre os diversos inversores instalados na micro rede (MG). A técnica de controle utilizada é o Controle Droop Generalizado (GDC) modificado para atender as necessidades de projeto, manter o equilíbrio entre a geração e o consumo com resposta rápida, segura, eficiente e estável. Neste cenário, seis estratégias de controle foram propostas e validadas para diferentes cenários de testes (cargas lineares e cargas não lineares) e topologias de micro redes (1 barra, 3 barras, 5 barras, 11 barras e 14 barras) sendo elas: GDC convencional, GDC ANFIS, GDC Fuzzy, GDC Adaptativo, PI Fuzzy e GDC Cooperativo com impedância virtual. A metodologia usada consistiu nas seguintes etapas: A) revisão da literatura; B) escolha das MG’s testes (padrão IEEE); C) modelagem e simulação das partes constituintes de uma MG isolada; D) projeto das estratégias de controle usadas na operação da MG; E) Validação das estratégias de controle; F) Discussão técnica dos resultados de simulação e G) Elaboração de documentos técnicos. Diante das estratégias de controle implementadas, o controlador GDC Adaptativo foi o que apresentou melhor desempenho dinâmico em malha fechada (rápido tempo de resposta, pequenas flutuações de tensão e frequência, pouca sensibilidade às flutuações da carga e da fonte energética, tornando o controle robusto e estável). Quando assistido pelas malhas internas consegue a cooperação de potência reativa e a compensação de harmônicos diante de flutuações de potência aparente tanto no consumo como na geração. As soluções propostas para regulação simultânea de tensão e frequência em MG isoladas, compensação harmônica de tensão no PCC e compartilhamento de potência reativa entre os inversores conectados na MG mostraram-se eficientes quando avaliadas em diversos cenários testes e para diversas topologias de MG, em termos de operação estável da MG, mantendo o equilíbrio entre a geração e o consumo, respondendo de forma rápida as variações operacionais, aos distúrbios de carga e as não linearidades da MG ilhada. / This work focuses on the proposal and validation of control strategies for simultaneous regulation of voltage and frequency in isolated Microgrid, voltage harmonics compensation in the common coupling point and the reactive power of cooperation between the different inverters installed in the Microgrid (MG). The used control technique is the modified generalized Droop control to meet the design needs (energy flow operation trafficked in MG), maintaining the balance between generation and consumption with rapid, safe, efficient and stable. In this scenario, six control strategies have been proposed and validated for different scenarios tests (linear and nonlinear loads) and topologies MG (1 bar, 3 bars, 5 bars, 11 bars and 14 bars) which are: conventional GDC, ANFIS GDC, GDC Fuzzy Adaptive GDC, GDC and PI Fuzzy Cooperative with virtual impedance. The methodology used consisted of the following steps: A) literature review; B) choice of MG tests (IEEE standard); C) modeling and simulation of the constituent parts of an isolated MG; D) design of the control strategies used in the MG operation; E) Validation of control strategies; F) Technical discussion of the simulation results and G) Elaboration of technical documents. Faced with the control strategies implemented, the GDC Adaptive controller showed the best dynamic performance in closed loop (fast response time, small fluctuations of voltage and frequency, low sensitivity to fluctuations in load and energy source, making the control robustness and stable). When assisted by internal loops, it achieves reactive power cooperation and harmonic compensation in the face of apparent power fluctuations in both consumption and generation. The proposed solutions for simultaneous regulation of voltage and frequency in isolated MG, harmonic voltage compensation in the PCC and reactive power sharing between the connected inverters in the MG were efficient when evaluated in several test scenarios and for several MG topologies in terms of stable MG operation, maintaining the balance between generation and consumption, responding quickly to the operational variations, load disturbances and nonlinearities of the islanded MG.

Workers who earn wage premiums for adverse job characteristics face a higher tax-price than peers of equal human capital working under more favorable conditions. Facing a higher cost per unit for public goods, they in turn demand a relatively small public sector. This may explain patterns of political affiliation across industries where differences in nonpecuniary aspects are often significant. I test this with county level data on fatality rates and support for the Republican candidate in the 2004 US Presidential election, finding that fatality rates remain positive and significant drivers of GOP support through various regression specifications. These results are robust to cross-sectional and panel data on individual contributions reported to the Federal Election Commission for the 2004, 2008, and 2012 US Presidential elections.

During a rocket launch, the point at which the most thrust is needed is at lift-off where the rocket is the heaviest since it is full of propellant. Unfortunately, this is also the point at which rocket engines perform the most poorly due to the relatively high atmospheric pressure at sea level. The Thrust Augmenting Nozzle (TAN) investigated in this paper provides a solution to this dilemma. By injecting extra propellant into the nozzle but downstream of the throat, the internal nozzle pressure is raised and the thrust is increased, and the nozzle efficiency, or specific impulse is potentially improved as well. Using this concept, the payload capacity of a launch vehicle can be increased and provides an excellent option for single stage to orbit vehicles.

To resolve the wage-risk trade off relationship on the labor market in Czech Republic, we introduce multiple hedonic wage regressions. Empirical theory ad- mits an income and age heterogeneity in value of a statistical life (VSL). This thesis employs a quantile regression along with age-dependent non-fatal and fa- tal on-the-job risk rates to estimate the age and income variation in VSL within a unified framework. Our results, based on EU-SILC 2018 data, implicate an inverted-V-shaped development of VSL with respect to age. The estimates of age-VSL peak for workers within the age cohort 42-47 across most real wage quantile levels and once reaching the maximum point the VSL proceeds to de- cline with age. In order to infer any effects of the global pandemic on VSL, we propose a set of novel COVID-19 control variables. Additionally, we annuitize the VSL estimates, which yields the value of a statistical life year (VSLY). The measures of VSLY correspond to the age and income varying trend of VSL. In conclusion, this thesis offers applicable varying VSL estimates across cohorts and wage distribution to policy-makers and respective authorities. JEL Classification J17, J24, J28, J31, J33 Keywords hedonic wage, compensating wage differential, quantile regression, VSL, income elasticity Title Measuring the...