Exploratory semiparametric analysis of two-dimensional diffusions in finance

We examine bivariate extensions of Aït-Sahalia’s approach to the estimation of univariate diffusions. Our message is that extending his idea to a bivariate setting is not straightforward. In higher dimensions, as opposed to the univariate case, the elements of the Itô and Fokker-Planck representations do not coincide; and, even imposing sensible assumptions on the marginal drifts and volatilities is not sufficient to obtain direct generalisations. We develop exploratory estimation and testing procedures, by parametrizing the drifts of both component processes and setting restrictions on the terms of either the Itô or the Fokker-Planck covariance matrices. This may lead to highly nonlinear ordinary differential equations, where the definition of boundary conditions is crucial. For the methods developed, the Fokker-Planck representation seems more tractable than the Itô’s. Questions for further research include the design of regularity conditions on the time series dependence in the data, the kernels actually used and the bandwidths, to obtain asymptotic properties for the estimators proposed. A particular case seems promising: “causal bivariate models” in which only one of the diffusions contributes to the volatility of the other. Hedging strategies which estimate separately the univariate diffusions at stake may thus be improved.

O trabalhador do terciário: sua representação do cotidiano, do trabalho e da sociedade

o tema pesquisado: "O trabalhador do Setor Terciário - sua representação do cotidiano, do trabalho e da sociedade" - é uma forma de explicitação de minha prática concreta. Compreender o terciário, a partir da ótica das relações de produção, para desvendar, ao nível da representação, como funciona o fetiche, ao nível através das explicações produzidas e do próprio discurso do trabalhador ligado a esta área de produção não material. Inicia-se por discutir as conjunturas brasileiras de trinta (1930) a oitenta (1980), para entender a oscilação entre o nacionalismo e o liberalismo econômico, entre o desenvolvimento nacional e o desenvolvimento associado ao capital estrangeiro. Estudam-se, neste contexto, diferentes explicações para a expansão do terciário, passando pela estrutura de ocupações, pelos seus efeitos marginais e pela divisão social do trabalho, onde o desenvolvimento e o subdesenvolvimento encontram sua funcionalidade no capitalismo em escala mundial. O estudo nos leva a compreender que todos estes acontecimentos de natureza sócio-econômica se refletem, não como relação mecânica, mas enquanto íntima articulação entre o sócio-político e o econômico. E esta indissociabilidade está viva na representação que o trabalhador faz do seu cotidiano, do trabalho e da sociedade, ainda que não se dê conta e que não possa desvendar o fetiche, o qual, no seu discurso e na sua consciência, revela e encobre a realidade ao mesmo tempo.

For profit social entrepreneurship: milestones to develop an efficient social venture

Inúmeras questões terríveis e alarmantes são ainda mal resolvidas, apesar da mobilização de ONGs para aliviá-los. Por muito tempo, o setor privado deu as costas a preocupações tal qual estas. Ate que um novo tipo de empreendedor revolucionário apareceu com um novo conceito para combater a pobreza. Mohamed Yunus desbravou empreendedorismo social quando criou a Grameen Bank 36 anos atrás: ele desafiou regras convencionais e estritas alugando dinheiro para Bengalis desmerecidos de credito, tudo isso obtendo lucro no mesmo tempo. Hoje, empreendedorismo social esta um fenômeno mas a maioria dos empreendedores do setor dos e meia ainda enfrentam dificuldades. A pesquisa acadêmica sobre o empreendedorismo social com fins lucrativos ainda está hesitante. O presente trabalho é uma modesta tentativa de analisar quais são os desafios que um empreendedor social com fins lucrativos enfrentará ao longo do caminho para criar seu empreendimento e sustentar os seus objetivos. O exame da literatura mostra que as dificuldades enfrentadas pelos empreendedores são devido a vários fatores, compreendo questões diretamente relacionadas a incerteza do mercado e o contexto local, questões organizacionais, de financiamento, de ética e questões relacionadas a resistência do modelo de negocio. As proposições derivando do exame da literatura foram confrontadas a casos concretos através de entrevistas com empreendedores sociais, investidores de impacto e instituições de apoio. Resultados da pesquisa corroboram as proposições do inicio mas enfatizam necessidade de resolver, com consideração cuidadosa, as questões relacionadas a incerteza do mercado e ao desenho duma governança adequada. A respeito da incerteza do mercado, a identificação das partes interessadas no empreendimento social e a adoção duma mentalidade eficaz para ajustar suposições iniciais para a realidade local, são um padrão chave de sucesso para o empreendimento social. No nível organizacional, a constituição dum time perito e comprometido junto com o desenho duma governança certa para equilibrar o desejo de obter lucro e a necessidade de sustentabilidade financeira é uma garantia de sucesso para o empreendedor social.

Non- parametric specification tests for conditional duration models

This paper deals with the estimation and testing of conditional duration models by looking at the density and baseline hazard rate functions. More precisely, we foeus on the distance between the parametric density (or hazard rate) function implied by the duration process and its non-parametric estimate. Asymptotic justification is derived using the functional delta method for fixed and gamma kernels, whereas finite sample properties are investigated through Monte Carlo simulations. Finally, we show the practical usefulness of such testing procedures by carrying out an empirical assessment of whether autoregressive conditional duration models are appropriate to oIs for modelling price durations of stocks traded at the New York Stock Exchange.

Aplicação de classificadores Bayesianos e regressão logística na análise de desempenho dos alunos de graduação

Este trabalho minera as informações coletadas no processo de vestibular entre 2009 e 2012 para o curso de graduação de administração de empresas da FGV-EAESP, para estimar classificadores capazes de calcular a probabilidade de um novo aluno ter bom desempenho. O processo de KDD (Knowledge Discovery in Database) desenvolvido por Fayyad et al. (1996a) é a base da metodologia adotada e os classificadores serão estimados utilizando duas ferramentas matemáticas. A primeira é a regressão logística, muito usada por instituições financeiras para avaliar se um cliente será capaz de honrar com seus pagamentos e a segunda é a rede Bayesiana, proveniente do campo de inteligência artificial. Este estudo mostre que os dois modelos possuem o mesmo poder discriminatório, gerando resultados semelhantes. Além disso, as informações que influenciam a probabilidade de o aluno ter bom desempenho são a sua idade no ano de ingresso, a quantidade de vezes que ele prestou vestibular da FGV/EAESP antes de ser aprovado, a região do Brasil de onde é proveniente e as notas das provas de matemática fase 01 e fase 02, inglês, ciências humanas e redação. Aparentemente o grau de formação dos pais e o grau de decisão do aluno em estudar na FGV/EAESP não influenciam nessa probabilidade.

An evaluation of the Business Model Canvas by technology-oriented startups in Brazil : a qualitative study about the usage of the tool by Brazilian entrepreneurs

The following paper was conducted with the support of several entrepreneurs and startups from Brazil. The aim of the research was to find out which impact the Business Model Canvas, further abbreviated as BMC, has on technology-oriented startups in Brazil. The first step of the study was identify some general concepts of entrepreneurship, as well as the conditions and environment of the country. Afterwards, it was focused on defining and comparing different business model tools and concepts to the BMC. After the literature review and meeting with several professionals in the area of entrepreneurship and startups, a questionnaire was formulated in order to conduct the qualitative study and identify the main impact of the tool. The questionnaire was answered by ten startups. In order to check the validity and credibility of the research outcomes, theory and investigator triangulation was used. As a result, the usage of the BMC could be evaluated by obtaining the outcomes and the theory, which showed that Brazilian tech startups are using Osterwalder’s model for the reason of idea creation and testing, validating and pivoting their business model. Interestingly, the research revealed that the entrepreneurs are using the tool often not in the traditional way of printing it, but rather applying it as a thinking approach. Besides, the entrepreneurs are focusing mostly on developing a strong Value Proposition, Customer Segment and sustainable Revenue Streams, while afterwards the remaining building blocks are built. Moreover, the research showed that the startups are using also other concepts, such as the Customer Development Process or Build-Measure-Learn Feedback Loop. These methodologies are often applied together with the BMC and helps to identify the most sustainable components of the business idea. Keywords: Business

Atividades educativas na prevenção da aids na rede básica municipal de saúde: participação do enfermeiro

TORRES, Gilson de Vasconcelos; ENDERS, Bertha Cruz. Atividades educativas na prevencao da AIDS em uma rede basica municipal de saude: participacao do enfermeiro. Rev.latino-am.enfermagem, Ribeirao Preto, v.7, n.2, p.71-77, abril 1999. Disponivel em: . Acesso em: 04 set. 2010.

Implementação de um Módulo de Supervisão para um Sistema de Detecção de Vazamentos em Dutos de Petróleo

The transport of fluids through pipes is used in the oil industry, being the pipelines an important link in the logistics flow of fluids. However, the pipelines suffer deterioration in their walls caused by several factors which may cause loss of fluids to the environment, justifying the investment in techniques and methods of leak detection to minimize fluid loss and environmental damage. This work presents the development of a supervisory module in order to inform to the operator the leakage in the pipeline monitored in the shortest time possible, in order that the operator log procedure that entails the end of the leak. This module is a component of a system designed to detect leaks in oil pipelines using sonic technology, wavelets and neural networks. The plant used in the development and testing of the module presented here was the system of tanks of LAMP, and its LAN, as monitoring network. The proposal consists of, basically, two stages. Initially, assess the performance of the communication infrastructure of the supervisory module. Later, simulate leaks so that the DSP sends information to the supervisory performs the calculation of the location of leaks and indicate to which sensor the leak is closer, and using the system of tanks of LAMP, capture the pressure in the pipeline monitored by piezoresistive sensors, this information being processed by the DSP and sent to the supervisory to be presented to the user in real time

Projeto, construção e análise de um prototipo vibracional em escala de bancada aplicável ao tratamento de água de produção de petróleo bruto, mediante inovadora operação híbrida de adsorção e auto-flotação

A self-flotator vibrational prototype electromechanical drive for treatment of oil and water emulsion or like emulsion is presented and evaluated. Oil production and refining to obtain derivatives is carried out under arrangements technically referred to as on-shore and off-shore, ie, on the continent and in the sea. In Brazil 80 % of the petroleum production is taken at sea and area of deployment and it cost scale are worrisome. It is associated, oily water production on a large scale, carrier 95% of the potential pollutant of activity whose final destination is the environment medium, terrestrial or maritime. Although diversified set of techniques and water treatment systems are in use or research, we propose an innovative system that operates in a sustainable way without chemical additives, for the good of the ecosystem. Labyrinth adsor-bent is used in metal spirals, and laboratory scale flow. Equipment and process patents are claimed. Treatments were performed at different flow rates and bands often monitored with control systems, some built, other bought for this purpose. Measurements of the levels of oil and grease (OGC) of efluents treaty remained within the range of legal framework under test conditions. Adsorbents were weighed before and after treatment for obtaining oil impregna-tion, the performance goal of vibratory action and treatment as a whole. Treatment technolo-gies in course are referenced, to compare performance, qualitatively and quantitatively. The vibration energy consumption is faced with and without conventional flotation and self-flotation. There are good prospects for the proposed, especially in reducing the residence time, by capillary action system. The impregnation dimensionless parameter was created and confronted with consecrated dimensionless parameters, on the vibrational version, such as Weber number and Froude number in quadratic form, referred to as vibrational criticality. Re-sults suggest limits to the vibration intensity

Saída compulsória do estrangeiro do território nacional à luz dos direitos humanos: análise de casos

This paper aims to review traditional concepts inherent to the general theory of the state and human rights, relating to the legal situation of foreign, understood as the subject of rights, especially when the is case of compulsory legal imposition of exit from national territory. After the serious violations during the Second World War and the importance acquired by the International Law of Human Rights, values as dignity, justice and equality are enshrined in the legal system and its respect required beyond the boundaries of any country. The creation of an international community, which is governed by rules that its members are subordinated, without distinction, as well as state - based on volunteerism, become inspired by one principled nature of these new concepts required of Global Society, as well as the adoption, influenced by neoconstitutionalism, to the model of State Constitutional rule of law, are opposed to the idea of state sovereignty connected to a superiority, absolute and unlimited power which recognizes no other above it, not even the basic principles or axioms that must govern the relationships internally. So looks for a concept of state that includes all the requirements of a democratic society, that have the people as the power holder, understanding that state element has undergone a relativization, because had to adapt to the contemporary values applicable to the individual, inserting in its concept, the indispensable obligation to protect the inalienable rights of citizens, regardless of with whom he have legal and political bond of nationality. It happens that, to consecrate these privileges to individuals, which, because they contain reference to values with supranational characteristics, are very abstract and are in constant collision course with internal rules, making it difficult to reconcile, it will use hermeneutics of human rights, due mainly to international courts, correlated with constitutional exegesis, in particular, legal principiologia, using, among others, the principles of reasonableness and proportionality, the systematic interpretation of the Constitution and international legal standards. Thus, it seek to enshrine the common foundation of all law , the link between the systems, namely, the dignity of human beings. Finally, it will see if Brazilian jurisdiction, through case studies, is tuned in line with these new paradigms, and in line with the International Bill of Human Rights, the Federal Constitution, the values and principles she hired

Um estudo sobre a aprendizagem de números irracionais no ensino médio

The present study describes theoretical practical relationships between development and application of activities in Mathematics education. It s proposed a methodological approach to Mathematics in the first grade of Ensino Médio, supported by an experiment involving Irrational Numbers education by using constructive activities, applied obeying an educational sequence. Constructivism is used as an important theoretical reference in teaching learning process of Mathematics. The methodological intervention was done with two classes of students of the first grade of Ensino Médio, in two public schools, a state one and a federal one, located on the city of Natal, Rio Grande do Norte. The development, application and testing of the activities used on this experiment led us to think more profoundly about the value of constructivism ideas and understand that the use of activities that obey an educational sequence favors the learning. It s also discussed the research results, commented on a way to contribute to the advances of the proposal and it s more constant use. The participation and testing of the students were analyzed and judged using Skemp s Instrumental Understanding and Relational Understanding concepts. The results of the research were considered good, so we believe this methodological intervention can be used more frequently in the classes of Ensino Médio and also be applied to teachers in courses of initial education and continuous formation

Aplicação do método de análise hierárquica na tomada de decisão para adoção de computação em nuvem: um estudo de caso na federação das indústrias do RN

The progresses of the Internet and telecommunications have been changing the concepts of Information Technology IT, especially with regard to outsourcing services, where organizations seek cost-cutting and a better focus on the business. Along with the development of that outsourcing, a new model named Cloud Computing (CC) evolved. It proposes to migrate to the Internet both data processing and information storing. Among the key points of Cloud Computing are included cost-cutting, benefits, risks and the IT paradigms changes. Nonetheless, the adoption of that model brings forth some difficulties to decision-making, by IT managers, mainly with regard to which solutions may go to the cloud, and which service providers are more appropriate to the Organization s reality. The research has as its overall aim to apply the AHP Method (Analytic Hierarchic Process) to decision-making in Cloud Computing. There to, the utilized methodology was the exploratory kind and a study of case applied to a nationwide organization (Federation of Industries of RN). The data collection was performed through two structured questionnaires answered electronically by IT technicians, and the company s Board of Directors. The analysis of the data was carried out in a qualitative and comparative way, and we utilized the software to AHP method called Web-Hipre. The results we obtained found the importance of applying the AHP method in decision-making towards the adoption of Cloud Computing, mainly because on the occasion the research was carried out the studied company already showed interest and necessity in adopting CC, considering the internal problems with infrastructure and availability of information that the company faces nowadays. The organization sought to adopt CC, however, it had doubt regarding the cloud model and which service provider would better meet their real necessities. The application of the AHP, then, worked as a guiding tool to the choice of the best alternative, which points out the Hybrid Cloud as the ideal choice to start off in Cloud Computing. Considering the following aspects: the layer of Infrastructure as a Service IaaS (Processing and Storage) must stay partly on the Public Cloud and partly in the Private Cloud; the layer of Platform as a Service PaaS (Software Developing and Testing) had preference for the Private Cloud, and the layer of Software as a Service - SaaS (Emails/Applications) divided into emails to the Public Cloud and applications to the Private Cloud. The research also identified the important factors to hiring a Cloud Computing provider

Mecanismos de segurança para um sistema cooperativo de armazenamento de arquivos baseado em P2P

Previous works have studied the characteristics and peculiarities of P2P networks, especially security information aspects. Most works, in some way, deal with the sharing of resources and, in particular, the storage of files. This work complements previous studies and adds new definitions relating to this kind of systems. A system for safe storage of files (SAS-P2P) was specified and built, based on P2P technology, using the JXTA platform. This system uses standard X.509 and PKCS # 12 digital certificates, issued and managed by a public key infrastructure, which was also specified and developed based on P2P technology (PKIX-P2P). The information is stored in a special file with XML format which is especially prepared, facilitating handling and interoperability among applications. The intention of developing the SAS-P2P system was to offer a complementary service for Giga Natal network users, through which the participants in this network can collaboratively build a shared storage area, with important security features such as availability, confidentiality, authenticity and fault tolerance. Besides the specification, development of prototypes and testing of the SAS-P2P system, tests of the PKIX-P2P Manager module were also performed, in order to determine its fault tolerance and the effective calculation of the reputation of the certifying authorities participating in the system

Utilização de redes neurais artificiais para detecção e diagnóstico de falhas

In a real process, all used resources, whether physical or developed in software, are subject to interruptions or operational commitments. However, in situations in which operate critical systems, any kind of problem may bring big consequences. Knowing this, this paper aims to develop a system capable to detect the presence and indicate the types of failures that may occur in a process. For implementing and testing the proposed methodology, a coupled tank system was used as a study model case. The system should be developed to generate a set of signals that notify the process operator and that may be post-processed, enabling changes in control strategy or control parameters. Due to the damage risks involved with sensors, actuators and amplifiers of the real plant, the data set of the faults will be computationally generated and the results collected from numerical simulations of the process model. The system will be composed by structures with Artificial Neural Networks, trained in offline mode using Matlab®

Desenvolvimento de um ambiente para projeto de controladores fuzzy para dispositivos móveis

Fuzzy intelligent systems are present in a variety of equipment ranging from household appliances to Fuzzy intelligent systems are present in a variety of equipment ranging from household appliances to small devices such as digital cameras and cell phones being used primarily for dealing with the uncertainties in the modeling of real systems. However, commercial implementations of Fuzzy systems are not general purpose and do not have portability to different hardware platforms. Thinking about these issues this work presents the implementation of an open source development environment that consists of a desktop system capable of generate Graphically a general purpose Fuzzy controller and export these parameters for an embedded system with a Fuzzy controller written in Java Platform Micro Edition To (J2ME), whose modular design makes it portable to any mobile device that supports J2ME. Thus, the proposed development platform is capable of generating all the parameters of a Fuzzy controller and export it in XML file, and the code responsible for the control logic that is embedded in the mobile device is able to read this file and start the controller. All the parameters of a Fuzzy controller are configurable using the desktop system, since the membership functions and rule base, even the universe of discourse of the linguistic terms of output variables. This system generates Fuzzy controllers for the interpolation model of Takagi-Sugeno. As the validation process and testing of the proposed solution the Fuzzy controller was embedded on the mobile device Sun SPOT ® and used to control a plant-level Quanser®, and to compare the Fuzzy controller generated by the system with other types of controllers was implemented and embedded in sun spot a PID controller to control the same level plant of Quanser®