Essays on economic growth

A fundamental question in development economics is why some economies are rich and others poor. To illustrate the income per capita gap across economies consider that the average gross domestic product (GDP) per capita of the richest 10 percent of economies in the year 2010 was a factor of 40-fold that of the poorest 10 percent of economies. In other words, the average person in a rich economy produces in just over 9 days what the average person in a poor economy produces in an entire year. What are the factors that can explain this difference in standard of living across the world today? With this in view, this dissertation is a conjunction of three essays on the economic growth field which we seek a possible responses to this question. The first essay investigates the existence of resource misallocation in the Brazilian manufacturing sector and measures possible distortions in it. Using a similar method of measurement to the one developed by Hsieh and Klenow (2009) and firm-level data for 1996-2011 we find evidence of misallocation in the manufacturing sector during the observed period. Moreover, our results show that misallocation has been growing since 2005, and it presents a non-smooth dynamic. Significantly, we find that the Brazilian manufacturing sector operates at about 50% of its efficient product. With this, if capital and labor were optimally reallocated between firms and sectors we would obtain an aggregate output growth of approximately 110-180% depending on the mode in which the capital share is measured. We also find that the economic crisis did not have a substantial effect on the total productivity factor or on the sector's misallocation. However, small firms in particular seem to be strongly affected in a global crisis. Furthermore, the effects described would be attenuated if we consider linkages and complementarity effects among sectors. Despite Brazil's well-known high tax burden, there is not evidence that this is the main source of resource misallocation. Moreover, there is a distinct pattern of structural change between the manufacturing sectors in industrialized countries and those in developing countries. Therefore, the second essay demonstrate that this pattern differs because there are some factors that distort the relative prices and also affect the output productivity. For this, we present a multi-sector model of economic growth, where distortions affect the relative prices and the allocation of inputs. This phenomenon imply that change of the production structure or perpetuation of the harmful structures to the growth rate of aggregate output. We also demonstrate that in an environment with majority decision, this distortion can be enhanced and depends on the initial distribution of firms. Furthermore, distortions in relative prices would lead to increases in the degree of misallocation of resources, and that imply that there are distinct patterns of structural changes between economies. Finally, the calibrated results of the framework developed here converge with the structural change observed in the firm-level data of the Brazilian manufacturing sector. Thereafter, using a cross-industry cross-country approach, the third essay investigates the existence of an optimal level of competition to enhance economic growth. With that in mind, we try to show that this optimal level is different from industrialized and under development economies due to the technology frontier distance, the terms of trade, and each economy's idiosyncratic characteristics. Therefore, the difference in competition industry-country level is a channel to explain the output for worker gap between countries. The theoretical and empirical results imply the existence of an inverted-U relationship between competition and growth: starting for an initially low level of competition, higher competition stimulates innovation and output growth; starting from a high initial level of competition, higher competition has a negative effect on innovation and output growth. Given on average industries in industrialized economies present higher competition level. With that if we control for the terms of trade and the industry-country fixed effect, if the industries of the developing economy operated under the same competition levels as of the industrialized ones, there is a potential increase of output of 0.2-1.0% per year. This effect on the output growth rate depends on the competition measurement used.

An essay on impression management: three randomized experiments with financial analysts

This thesis aims to explore the concept of impression management from the financial analysts’ point of view. Impression management is the definition of the act of an agent manipulating an impression that another person have of this agent, in the context of this thesis it happens when a company make graphics to disclosure financial-accounting information in order to manipulate the market’s perception of their performance. Three types of impression management were analyzed: presentation enhancement (color manipulation), measurement distortion (scale manipulation) and selectivity (the disclosure of positive information only). While presentation enhancement improved only the most impulsive financial analysts’ perception of firm’s performance, the measurement distortion improved the perception of performance for both groups of financial analysts (impulsive and reflective). Finally, selectivity improved the financial analysts’ perception of firm’s performance for both groups (impulsive and reflective), although impulsive financial analysts assigned lower ratings when compared to their reflective peers, on average, to a hypothetical company.

Inexpensive solution for real-time video and image stitching

Image stitching is the process of joining several images to obtain a bigger view of a scene. It is used, for example, in tourism to transmit to the viewer the sensation of being in another place. I am presenting an inexpensive solution for automatic real time video and image stitching with two web cameras as the video/image sources. The proposed solution relies on the usage of several markers in the scene as reference points for the stitching algorithm. The implemented algorithm is divided in four main steps, the marker detection, camera pose determination (in reference to the markers), video/image size and 3d transformation, and image translation. Wii remote controllers are used to support several steps in the process. The built‐in IR camera provides clean marker detection, which facilitates the camera pose determination. The only restriction in the algorithm is that markers have to be in the field of view when capturing the scene. Several tests where made to evaluate the final algorithm. The algorithm is able to perform video stitching with a frame rate between 8 and 13 fps. The joining of the two videos/images is good with minor misalignments in objects at the same depth of the marker,misalignments in the background and foreground are bigger. The capture process is simple enough so anyone can perform a stitching with a very short explanation. Although real‐time video stitching can be achieved by this affordable approach, there are few shortcomings in current version. For example, contrast inconsistency along the stitching line could be reduced by applying a color correction algorithm to every source videos. In addition, the misalignments in stitched images due to camera lens distortion could be eased by optical correction algorithm. The work was developed in Apple’s Quartz Composer, a visual programming environment. A library of extended functions was developed using Xcode tools also from Apple.

Análise microestrutural de misturas cerâmicas de grês porcelanato com adição de chamote de telhas cerâmicas

MELO, Maxymme Mendes de ; PINHEIRO, Andrea Santos ; NASCIMENTO, R. M. ; MARTINELLI, Antonio Eduardo ; DUTRA, Ricardo Peixoto Suassuna ; MELO, Marcus Antônio de Freitas . Análise microestrutural de misturas cerâmicas de grês Porcelanato com adição de chamote de telhas cerâmicas. Cerâmica (São Paulo. Impresso), v. 55, p. 356-364, 2009

Caracterização microestrutural e elétrica de La(FexNi1-x)O3 sintetizado pelo método da gelatina

The present work deals with the synthesis of materials with perovskite structure with the intention of using them as cathodes in fuel cells SOFC type. The perovskite type materials were obtained by chemical synthesis method, using gelatin as the substituent of citric acid and ethylene glycol, and polymerizing acting as chelating agent. The materials were characterized by X-ray diffraction, thermal analysis, spectroscopy Fourier transform infrared, scanning electron microscopy with EDS, surface area determination by the BET method and Term Reduction Program, TPR. The compounds were also characterized by electrical conductivity for the purpose of observing the possible application of this material as a cathode for fuel cells, solid oxide SOFC. The method using gelatin and polymerizing chelating agent for the preparation of materials with the perovskite structure allows the synthesis of crystalline materials and homogeneous. The results demonstrate that the route adopted to obtain materials were effective. The distorted perovskite structure have obtained the type orthorhombic and rhombohedral; important for fuel cell cathodes. The presentation material properties required of a candidate cathode materials for fuel cells. XRD analysis contacted by the distortion of the structures of the synthesized materials. The analyzes show that the electrical conductivity obtained materials have the potential to act as a cell to the cathode of solid oxide fuel, allowing to infer an order of values for the electrical conductivities of perovskites where LaFeO3 < LaNiO3 < LaNi0,5Fe0,5O3. It can be concluded that the activity of these perovskites is due to the presence of structural defects generated that depend on the method of synthesis and the subsequent heat treatment

Estudo da síntese e propriedade magnética de ferritas de manganês/cobalto dopadas com níquel

For the chemical method of synthesis of co-precipitation were produced ferrite powders manganese-cobalt equal stoichiometric formula Mn (1-x) Co (x) Fe2O4, for 0 < x < 1, first reagent element using as the hydroxide ammonium and second time using sodium hydroxide. The obtained powders were calcined at 400 ° C, 650 ° C, 900 ° C and 1150 ° C in a conventional oven type furnace with an air atmosphere for a period of 240 minutes. Other samples were calcined at a temperature of 900 ° C in a controlled atmosphere of argon, to evaluate the possible influence of the atmosphere on the final results the structure and morphology. The samples were also calcined in a microwave oven at 400 ° C and 650 ° C for a period of 45 minutes possible to evaluate the performance of this type of heat treatment furnace. It was successfully tested the ability of this group include isomorphic ferrite with the inclusion of nickel cations in order to evaluate the occurrence of disorder in the crystalline structures and their changes in magnetic characteristics.To identify the structural, morphological, chemical composition and proportions, as well as their magnetic characteristics were performed characterization tests of X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDX), thermogravimetric (TG), vibrating sample magnetometry (MAV) and Mössbauer spectroscopy. These tests revealed the occurrence of distortion in the crystal lattice, changes in magnetic response, occurrence of nanosized particles and superparamagnetism

Influência da lubrirrefrigeração na qualidade superficial de metais retificados

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Inclusão digital: a inserção das tecnologias informacionais nas escolas públicas da RMNatal

This study aims to determine the influence of Digital Inclusion in school performance of students from public high school in the metropolitan area of Natal, through the use of computers in a pedagogical and Internet use.Throughout the paper we try to answer the question: The pedagogical use of computers connected to the Internet contributes to improving the academic performance of students in public schools in the RMNatal? To answer the research question, we focus on the database INEP on the infrastructure of schools and the bank rates of school performance. For both technical procedures performed to obtain the relationship between Internet and School Performance. Then the School Settings have been configured for Digital Inclusion and made crosses with the approval rates, distortion and failure. The survey results indicate that according to the classification established in: Included in School Settings, School Settings deficit, Adverse Environments School and School Settings Deleted, which has prevailed in the metropolitan area of Natal are the schools that are provided outside.

Gestão de centros históricos: uma avaliação da política de requalificação urbana de Natal/RN

From the second half of the century XX, in many Brazilian cities, the "historic centers" stop being the most densely populated areas of the city, accumulate degradation of the built environment and its functions have physical, social and economic resignified when also intensified interventions in these same centers Historic focused its redevelopment. This work aims to reflect on the experience of urban regeneration in the historic center of Natal, addressing the strategies adopted in the implementation of public policies and how these improve the effectiveness of actions, processes and outcomes for which turn the management of the historic center in question. In Natal, is identified in the neighborhoods of the Upper Town and Ribeira, the historic city center, a large distortion of their ancient architectural complex, the use of sub-urban infrastructure and emptying in the evenings and weekends. Shares redevelopment of the historic center of Natal are considered late, it is only recently that these neighborhoods were objects of policies and projects generally aimed at enhancing the cultural attraction of the area, and not always, it can be said that they have relevance in development process of the city. Added to this, there is the slowness of the interventions, although the zoning as an area of historic preservation has been done for over two decade. In Natal, the ideas of sustainable development articulated a proposed redevelopment of its historic center is still far from being achieved, but on the other hand, the latest phase of implementation of plans and projects in the area, indicating the intention to transform practical experience in the formulations and proposals in relation to these ideals

Ativismo ministerial na implementação de políticas públicas

The research aims to analyze the reasons and the unique role of prosecutors in the promotion of public policies. The opening lines deal with the evolution and expansion of the general theory of the fundamental rights in the international and national levels and that have led to the creation of a welfare state concerned with carrying out positive actions which aim at the community well-being. Thus, it is clear that, after the uneven development of the Brazilian democracy, the Constitution of 1988 not only has erected to a state socially responsible, but also built a system of guarantees which highlights the significant expansion of the Powers of the Public Ministry and has now taken an outstanding position in regard to collective rights, allowing, at the same time, its members to perform the syndication of state actions, particularly public policies, correcting the course of these administrative processes in the presence of poor management and inactivity of the public administrator when acting in defense of fundamental rights. This ministerial activism, even facing the obstacles and boundaries submitted to its pursuit, has shown an increase in actions that culminated, in the last ten years, in a significant number of judicial and extrajudicial measures that indicated the correction of public policies and actions in areas of health, education, housing and the environment. In this process of monitoring and doing, the important role of the other social characters is highlighted, especially the one of the citizen who is responsible for most of the complaints that start the initiatives of the Public Ministry and that can be deployed through a significant list of judicial and extrajudicial instruments, especially the important procedure that allows the hearing and participation of the involved in the implementation of public policies, enabling a collective even a consensual solution of the matter generated among the Public Administration. Given these initiatives, the ministerial activism has established itself as a movement of its own characteristics, aimed to guarantee the fundamental rights, especially when these are not targeted by state actions that should contribute to the achievement of the democratic state of law idealized by the Federal Constitution without any distortion of direction. Nevertheless, this activism still seeks for its full accomplishment in the practical world

Iniciativa popular na concretização do direito fundamental à democracia

The Participatory Democracy is disseminated throughout the Principle of Popular Sovereignty. Since it spurs the participation of the people in the exercise of political power, it emerges as a conciliatory alternative to the Representative Regime - one of questionable legitimacy in account of the distortion it causes on the will of the public. It does so specially vis-à-vis the legislative, where the law is created. It s known that our Constitution (arts. 1º e 14, CF/88) provides for the means through which the members of the public may take part in the political process of the country, for it consecrates the plebiscite, the referendum and the popular initiative, all of them incipiently regulated by the Lei nº 9.709/98. It s our task, thus, to inquire, through deductive reasoning as well as the legal exegeses, the enforceability of the Popular Initiative as a means of popular emancipation, given that it enables the citizens to conscientiously participate in the public sphere. It has also an educational ethos which builds the capacity of individual to act, and, therefore, through thoughtful choices, enhance the legal system. Furthermore, the Lei da Ficha Limpa (LC nº 135/2010) surely represents a milestone in the Brazilian political history, since it accrued from a new way of social interaction allowed by the usage of communication technology on the pursuit of political morality. As a matter of fact, this bill is a clear example of how a legal act was legitimately proposed through Public Initiative. Hence, it s beneficial to actually make use of the Public Initiative, under the influence of the New Constitutional Hermeneutics, with a view to supporting social claims and promoting a dialogical relationship with the State in order to help it in the decisionmaking process. Thereat, we can achieve important civic spaces through which the fundamental right to democracy shall be materialized, tearing apart the old paradigms of inequality and, thus, promoting social justice

Técnica de controle adaptativo robusto aplicada a filtros ativos de potência e paralelo

The Methods for compensation of harmonic currents and voltages have been widely used since these methods allow to reduce to acceptable levels the harmonic distortion in the voltages or currents in a power system, and also compensate reactive. The reduction of harmonics and reactive contributes to the reduction of losses in transmission lines and electrical machinery, increasing the power factor, reduce the occurrence of overvoltage and overcurrent. The active power filter is the most efficient method for compensation of harmonic currents and voltages. The active power filter is necessary to use current and voltage controllers loop. Conventionally, the current and voltage control loop of active filter has been done by proportional controllers integrative. This work, investigated the use of a robust adaptive control technique on the shunt active power filter current and voltage control loop to increase robustness and improve the performance of active filter to compensate for harmonics. The proposed control scheme is based on a combination of techniques for adaptive control pole placement and variable structure. The advantages of the proposed method over conventional ones are: lower total harmonic distortion, more flexibility, adaptability and robustness to the system. Moreover, the proposed control scheme improves the performance and improves the transient of active filter. The validation of the proposed technique was verified initially by a simulation program implemented in C++ language and then experimental results were obtained using a prototype three-phase active filter of 1 kVA

Antenas monopolo planar com patch em anel circular para sistemas UWB

The microstrip antennas are largely used in wireless communication systems due to their low cost, weight, less complex construction and manufacturing, in addition to its versatility. UWB systems have emerged as an alternative to wireless communications over short distances because they offer of higher capacity and lower multipath distortion than other systems with the same purpose. Combining the advantages of microstrip antennas to the characteristics of UWB, it is possible to develop more and more smaller devices, with diverse geometries to operate satisfactorily in these systems. This paper aims to propose alternatives to microstrip antennas for UWB systems operate in the range between 3.1 and 10.6 GHz, with a patch on circular ring. Some techniques are analyzed and employed to increase the bandwidth of proposed antenna: the insertion of a parasitic elements and a rectangular slit in the displaced ground plane. For this, key issues are presented as the basic principles of UWB systems, the fundamental theory of antennas and microstrip antennas. The simulations and experimental characterization of constructed antennas are presented, as well as analysis of parameters such as bandwidth and radiation pattern

Obtenção dos parâmetros-x de estruturas planares

Due to major progress of communication system in the last decades, need for more precise characterization of used components. The S-parameters modeling has been used to characterization, simulation and test of communication system. However, limitation of S-parameters to model nonlinear system has created new modeling systems that include the nonlinear characteristics. The polyharmonic distortion modeling is a characterizationg technique for nonlinear systems that has been growing up due to praticity and similarity with S-parameters. This work presents analysis the polyharmonic distortion modeling, the test bench development for simulation of planar structure and planar structure characterization with X-parameters

Contribuições ao método de rastreamento de máxima potência para sistemas fotovoltaicos

The scarcity of natural resources and the search for alternative energy sources promote a rapid change in the energy world. Among the renewable energy sources, solar energy is the most promising, presenting technology of greatest growth rate nowadays. Researchers around the world are seeking ways to facilitate their progress, developing technologies with higher efficiency and lower cost. As a contribution to global progress, this master thesis proposes the development of a strategy of maximum power tracking based on perturbation and observation method for photovoltaic systems. The proposed control strategy is based on active power balance of the system, with a reduced number of sensors. It also allows the PV system to act as a regulator of the power quality at the point of commom coupling (PCC), compensating the harmonic distortion and power factor of the current netw