Estudo do caso de falência da VARIG à luz da Cadeia de Valor de Porter

Dissertação (mestrado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Civil e Ambiental, 2019.Nas últimas décadas, a participação do transporte aéreo regular no deslocamento interestadual de passageiros tem apresentado considerável crescimento no território brasileiro, superando, desde 2010, a participação do modo rodoviário (ANAC, 2018). Na contramão desse protagonismo, as empresas do setor vêm acumulando prejuízos que superam os 16 bilhões de reais. Caso esse cenário não se altere, é possível que algumas das maiores companhias aéreas atualmente no mercado brasileiro venham a colapsar, comprometendo o futuro da Aviação Civil no Brasil. É relevante observar, ainda, que os impactos deletérios da falência de uma empresa aérea para os passageiros e para a economia nacional podem ser perenes. Assim, compreender adequadamente o fenômeno que levou as companhias aéreas ao colapso – verificando de maneira isenta e adequada quais fatores contribuintes foram determinantes para tal – é estratégico para as empresas e Autarquias ligadas ao setor. Com esse intuito, o trabalho apresenta uma abordagem sobre os principais conceitos teóricos relativos à Teoria da Organização Industrial, com destaque para a Teoria da Cadeia de Valor de Porter (1989), seguida de uma síntese dos principais fatos históricos da trajetória da VARIG. Traz, ainda, a cadeia de valor de Porter (1989) aplicada ao caso da VARIG, como método para a avaliação de desempenho dos custos e da lucratividade da organização, por meio da identificação de suas atividades de valor e suas respectivas análises, sendo discutidas as conclusões no capítulo derradeiro deste trabalho.In the last decades, the share of air transportation in interstate displacement of passengers has presented a considerable growth in Brazilian territory, surpassing, since 2010, the participation of the roadway participation (ANAC, 2018). Contrary to this role, companies in the sector have accumulated losses that exceed R$16 billion. If this scenario does not change, there is a possibility that some of the largest airlines currently in the Brazilian market will collapse, compromising the future of Civil Aviation in Brazil. It is also important to note that the deleterious impacts of an airline's bankruptcy on passengers and the national economy can be perennial. Thus, properly understand the phenomenon that led airlines to collapse - checking of free and fair manner which contributing factors - were instrumental in the setting achieved is strategic for companies and authorities related to the sector. With this aim this Thesis presents an approach on the main theoretical concepts related to Industrial Organization Theory, with emphasis on Porter's Value Chain Theory (1989), followed by a synthesis of the main historical facts of the VARIG trajectory. It also brings the value chain of Porter (1989) applied to the VARIG case, as a method to evaluate the performance of costs and profitability of organization, through the identification of their value activities and their respective analyzes and discuss the conclusions in the last chapter of this work

Development of a forced-convection gas target for improved thermal performance

Introduction The internal pressure experienced by a gas tar-get during irradiation is dependent on the beam energy deposited in the target, the beam cur-rent, and the thermal behaviour of the target. [1] The maximum beam energy deposited is a function of the cyclotron capabilities and the gas inventory within the target. The maximum beam current is limited by the pressure produced in the target and the ability of the target assembly to remain intact. This is also a function of the thermal behaviour of the target, which is difficult to predict a priori since it is dependent on such things as convection currents that occur during irradiation. We conducted bench tests with model gas targets with and without forced convection currents to observe the effect on thermal behaviour. Based on those results we constructed a prototype gas target, suitable for irradiation, with an internal fan assembly that is rotated via external magnets. Material and Methods Bench tests were conducted with cylindrical and conical target bodies of aluminum. A nickel-chromium heater wire was inserted into the gas volume through the normal beam entrance port (FIGURE 1) to heat the gas while water cooling was applied to the target body. The voltage and current of the heater coil was monitored along with the pressure inside the target and the water inlet and outlet temperature. In the case of tests with a driven fan blade either the voltage applied to the electric motor was monitored or the fan speed itself was recorded. By assuming the ideal gas law, the pressure gives the average bulk temperature and a global heat transfer coefficient can be calculated between the target gas and the cooling water. [2] A cylindrical target body was constructed that incorporated a fan blade driven by an external motor. This assembly used a simple o-ring seal on the rotating shaft. This seal was not robust enough for any tests under beam conditions. A prototype design suitable for in-beam operation employs a propeller mounted on a rotating disc housing two samarium cobalt magnets and spinning on two micro-bearings which are constructed to operate in high temperature environments. The micro-bearings are mounted on a pin projecting from a plate welded to the back of the gas target to allow assembly of the fan mechanism prior to attachment to the body (FIGURE 2)

Interações mediadas pela tecnologia em sala de aula: o uso das redes sociais e a exclusão digital

The National Program for Access to Secondary Education and Employment (Pronatec), created by the federal government has offered, in recent years, training in technical courses at post-secondary level for young people and adults inserted in the educational system and who were attending or finishing high school, including the Youth and Adult Education system (EJA). Thus, some classes of technical courses presented a varied profile of students from teenagers who attend public schools and even older adults who are returning to school after years of absence from the education system. The present study analyzed four groups of students aged between 15 and 63 years. This age difference, how the oldest students use or not technology and the kind of relationship between the students in the classroom raised questions about their relationship on social networks. This network usage by the students significantly influenced the pedagogical practice during the course, considering that the students asked the teacher to use it as a teaching and learning resource. The students transit from reality to virtual world with the naturalness of people who were born inserted in this context of interactions mediated by technology.El programa nacional de acceso a la escuela secundaria y el empleo (PRONATEC) del gobierno federal ha ofrecido, en los últimos años, capacitación en cursos técnicos a nivel pós-Lezíria para jóvenes y adultos insertados en el sistema educativo y que asisten o terminan la escuela secundaria, incluyendo El sistema de Educación de los jóvenes y adultos (eja). Con esto, algunas clases de cursos técnicos presentaron un perfil variado de alumnos, desde adolescentes que asisten a escuelas públicas hasta adultos mayores, que regresan a bancos escolares después de años de distanciamiento del sistema docente. En este estudio se analizaron cuatro clases de PRONATEC con alumnos de entre 15 y 63 años de edad. Esta diferencia, así como la forma en que los estudiantes de más edad utilizan la tecnología o no y cómo la relación entre los estudiantes de los perfiles tan diversos se establecieron en el aula, planteó preguntas sobre el camino de las relaciones en las redes sociales, ya que estas redes Impregnaron la práctica pedagógica durante el curso, a petición de estudiantes, estudiantes que transitan de la realidad a lo virtual con la naturalidad de aquellos que nacieron insertados en este contexto de interacciones mediadas por la tecnología.O Programa Nacional de Acesso ao Ensino Médio e Emprego (Pronatec) do Governo Federal ofereceu, nos últimos anos, formação em cursos técnicos em nível pós-médio para jovens e adultos inseridos no sistema educacional e que estivessem cursando ou concluindo o Ensino Médio, inclusive pelo sistema de Educação de Jovens e Adultos (EJA). Com isso, algumas turmas dos cursos técnicos apresentaram um variado perfil de alunos, desde adolescentes que estão frequentando as escolas públicas até adultos mais velhos, que estão retornando aos bancos escolares depois de anos de afastamento do sistema de ensino. No presente estudo foram analisadas quatro turmas do Pronatec com alunos com idades entre 15 e 63 anos. Essa diferença, bem como a forma como os alunos mais velhos utilizavam a tecnologia ou não e como o relacionamento ente os estudantes de perfis tão diversos se estabelecia em sala de aula, suscitou questionamentos sobre o modo de relacionamento nas redes sociais, uma vez que essas redes permearam a prática pedagógica durante o curso, a pedido dos alunos, alunos estes que transitam da realidade para o virtual com a naturalidade de quem nasceu inserido neste contexto de interações mediadas pela tecnologia.

Monte-Carlo simulation with FLUKA for liquid and solid targets

Introduction Monte-Carlo simulations can be used to assess isotope production on small medical cyclotrons. These simulations calculate the particle interactions with electric and magnetic fields, as well as the nuclear reactions. The results can be used to predict both yields and isotopic contaminations and can aid in the optimum design of target material and target geometry [1,2]. FLUKA is a general-purpose tool widely used in many applications from accelerator shielding to target design, calorimetry, activation, dosimetry, detector design, neutrino physics, or radiotherapy [3,4]. In this work, we applied the Monte-Carlo code FLUKA to determine the accuracy of predicting yields of various isotopes as compared to experimental yields. Material and Methods The proton beam collimation system, as well as the liquid and solid target of the TR13 cyclotron at TRIUMF, has been modeled in FLUKA. The proton beam parameters were initially taken from the cyclotron design specifications and were optimized against experimental measurements from the TR13. Data from irradiations of different targets and with different beam currents were collected in order to account for average behavior, see FIG. 1. Yields for a pencil proton beam as well as a beam spread out in direction and energy have been calculated and have been compared to experimental results obtained with the TR13. Results and Conclusion The reactions listed in TABLE 1 were assessed. For most reactions a good agreement was found in the comparison between experimental and simulated saturation yield. TABLE 1 only shows the yields simulated with a proton beam with a spread in both direction and energy. In most cases, the simulated yield is slightly larger or comparable. Only the calculated yield for 55Co was significantly lower by a factor of 4.2. This is still a good agreement considering that FLUKA was originally a high-energy physics code. It may indicate that the FLUKA internal cross-section calculation for this isotope production needs some optimization. In summary, we conclude that FLUKA can be used as a tool for the prediction of isotope production as well as for target design

Production of radiometals in a liquid target

Introduction Access to radiometals suitable for labeling novel molecular imaging agents requires that they be routinely available and inexpensive to obtain. Proximity to a cyclotron center outfitted with solid target hardware, or to an isotope generator for a radiometal of interest is necessary, both of which can be significant hurdles in availability of less common isotopes. Herein, we describe the production of 44Sc, 68Ga, 89Zr, 86Y and 94mTc in a solution target which allows for the production of various radiometallic isotopes, enabling rapid isotope-biomolecule pairing optimization for tracer development. Work on solution targets has also been performed by other groups [e.g. 1, 2]. Material and Methods Solutions containing a high concentration of natural-abundance zinc nitrate, yttrium nitrate, calcium nitrate [3], strontium nitrate or ammonium heptamolybdate [4] were irradiated on a 13 MeV cyclotron using a standard liquid target. Some of the solutions contained additional hydrogen peroxide or nitric acid to improve solubility and reduce pressure rise in the target during irradiation. Yields calculated using theoretical cross sections (EMPIRE [5]) were compared to the measured yields. In addition, we tested a thermo-syphon target design for the production of 44Sc. Chemical separation of the product from the target material was carried out on a remote apparatus modeled after that of Siikanen [6]. Results and Conclusion The proposed approach enabled the production of quantities sufficient for chemical or biological studies for all metals discussed. In the case of 68Ga, activity up to 480 ± 22 MBq was obtained from a one hour run with a beam current of 7 µA, potentially enabling larger scale clinical production. Considering all reactions, the ratio of theoretical saturation yields to experimental yields ranges from 0.8 for 94mTc to 4.4 for 44Sc. The thermo-syphon target exhibited an increase of current on the target by a factor of 2.5 and an increase in yield by a factor of five for the production of 44Sc. Separation methods were developed for all isotopes and separation efficiency ranges from 71 ± 1 % for 94mTc to 99 ± 4 % for 86Y. 44Sc, 68Ga, and 86Y were successfully used in labeling studies with a model 1,4,7,10-tetrazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) chelate, while 89Zr coordination behavior was tested using desferrioxamine-alkyne (DFO-alkyne). In summary, we present a promising new method to produce a suite of radiometals in a liquid target. Future work will continue to expand the list of radiometals and to apply this approach to the development of various peptide, protein and antibody radiotracers

Research On Zinc Blood Levels And Nutritional Status In Adolescents With Autoimmune Hepatitis.

Zinc deficiency in children and adolescents impairs their growing, development and immune system. To verify the existence of plasma and leukocyte zinc deficiency in adolescents with autoimmune hepatitis. The study comprised 23 patients with autoimmune hepatitis, aged 10-18 years, assisted at the Ambulatory Service of Pediatric Hepatology of the University of Campinas Teaching Hospital, Campinas, SP, Brazil, and adolescents with ages compatible with the patients' ages comprised the control group. Sample of blood in both groups was collected for the analyses of plasma zinc and leukocyte zinc by atomic absorption spectrophotometry, beyond the nutritional status was evaluated in each adolescent. The following statistical tests were used: Mann-Whitney, Spearman's correlation and interclass concordance analysis. The significance level adopted was 5%. The average zinc level in plasma in patients was 71.91 ± 11.79 µg/dL and, in the control group, it was 80.74 ± 10.92 µg/dL, showing a significant difference (P = 0.04). The leukocyte zinc level in patients was 222.33 ± 166.13 pmol/10⁶ cells and, in the control group, it was 226.64 ± 217.81 pmol/10⁶ cells; there was no statistical significance between them (P = 0.45). The evaluation of the nutritional status showed that eutrophy is prevalent in patients, and they presented a higher body fat value than the control group, with a significant difference. More research is needed with adolescents with autoimmune hepatitis regarding levels of essential micronutrients, such as zinc, because a good nutritional status can improve the prognostic of liver disease.4862-

Rapid quantitative turbidimetric spot test analysis of potassium in blood serum

A spot test quantitative turbidimetric method was developed for the determination of potassium in blood serum. The precipitation of potassium is done in basic medium with the classical analytical reagent sodium tetraphenylborate. The measurement of the turbidity is directly performed in this solution without further dilution using a micro-turbidimetric cell developed in this work. Blood serum was mixed with the buffer and the analytical reagent solution. The turbidity is measured in a spectrophotometer at 700 nm. The calibration curve is a straight line in the working concentration range, presenting a correlation coefficient equal to 0.9998. The analytical results obtained with this method were compared with those obtained through the use of a potassium ion selective electrode. Complete agreement was achieved between the two methods at the 99% confidence level. The observed mean RSD was 3.8%.Um método micro-analítico, spot-test foi desenvolvido para a determinação de potássio em soro sangüíneo. A precipitação de potássio é feita em meio alcalino com o reagente tetrafenilborato de sódio. A medida turbidimétrica é realizada diretamente com esta solução, sem a necessidade de diluição, usando uma micro-cela turbidimétrica desenvolvida neste trabalho. O soro sangüíneo é misturado com o tampão e a solução do regente analítico. A turbidância é medida num espectrofotômetro à 700 nm. A curva de calibração é uma linha reta, na faixa de concentração de trabalho. O coeficiente de correlação é 0,9998. Os resultados analíticos obtidos com este método foram comparados com aqueles obtidos usando eletrodo seletivo de potássio. Foi observada total concordância entre os dois métodos num nível de confiança de 99%. O desvio padrão relativo médio obtido foi 3,8%.63563

Perfil da prática de exercícios físicos e estilo de vida em adultos com distúrbio de sono

Objetivo: Descrever as características do estilo de vida e prática de exercícios físicos de indivíduos com distúrbios do sono. Método: Os sujeitos do presente estudo são 14 pacientes adultos, portadores de distúrbio de sono, sendo 10 do sexo masculino e 04 do sexo feminino, de uma clínica de polissonografia de Santa Cruz do Sul-RS. Para a coleta de dados, foi utilizado um questionário com questões referentes ao estilo de vida, saúde e bem-estar, adaptado de Barros e Nahas1 e também um questionário de escala de sonolência de Epworth. Resultados e considerações finais: Os resultados da pesquisa demonstraram uma frequência considerável de estresse, de sedentarismo e elevado índice de massa corporal dos sujeitos investigados, sugerindo, desta forma, que pode haver relação entre esses elementos e os distúrbios do sono

Prevalência de obesidade e hipertensão arterial em escolares: estudo comparativo entre escolas rurais do município de Santa Cruz do Sul/RS

Backgound and Objectives: The prevalence of obesity in children and adolescents has increased significantly all over the world. Consequently, the prevalence of diseases that were once considered adult, has also affected young, increasingly early. To investigate whether there are differences in the rates of obesity and hypertension among schoolchildren of the Northern hemisphere, south, east and west of the rural municipality of Santa Cruz do Sul-RS. Methods: A cross-sectional study involved students, aged 7-17 years, from 5 schools in the rural municipality of Santa Cruz do Sul- RS. Anthropometric indices such as BMI (body mass index), WC (waist circumference), %BF (body fat percentage) and both systolic blood pressure (SBP) and diastolic (DBP) were evaluated. Data were analyzed using the SPSS 20.0 program through descriptive analysis and chi-square test, considering significant differences p≤0,005. Results: Were evaluated 726 students, 350 male and 376 female. Prevalence rates in five schools assessed were similar, except for the fat percentage, where the school 3 presented significantly higher prevalence of elevated %BF for both male and female. Conclusion: The closest school urban area showed the highest prevalence of elevated %BF, the other parameters prevalence rates were similar. KEYWORDS: Obesity. Hypertension. Child. Adolescent. Rural Population.Justificativa e Objetivos: A prevalência de obesidade em crianças e adolescentes tem aumentado de forma significativa em todo o mundo. Em consequência, as prevalências de doenças, antes considerada de adultos, também tem acometido jovens, cada vez mais cedo. Diante disto, o presente estudo pretende investigar se há diferenças nos índices de obesidade e hipertensão arterial, entre escolares dos hemisférios norte, sul, leste e oeste da zona rural do município de Santa Cruz do Sul/RS. Métodos: Trata-se de um estudo descritivo-comparativo, exploratório, com abordagem quantitativa realizada com escolares, com idades entre 7 e 17 anos, de cinco escolas da zona rural do município de Santa Cruz do Sul/RS. Foram avaliados índices antropométricos como o IMC (índice de massa corporal), CC (circunferência da cintura), %G (percentual de gordura) e pressão arterial, tanto sistólica (PAS) como diastólica (PAD). Os dados foram analisados no programa SPSS 20.0, através de análise descritiva e teste do qui-quadrado, considerando diferenças significativas para p≤0,05. Resultados: Foram avaliados 726 escolares, sendo 350 do sexo masculino e 376 do sexo feminino. As prevalências encontradas nas 5 escolas avaliadas foram semelhantes, com exceção para o percentual de gordura, onde a escola 3 apresentou maior prevalência de percentual de gordura elevado, tanto para o sexo masculino, quanto para o feminino. Conclusão: A escola mais próxima da zona urbana foi a que apresentou maior prevalência de percentual de gordura elevado, nos demais parâmetros as prevalências encontradas foram semelhantes. DESCRITORES: Obesidade. Hipertensão. Crianças. Adolescentes. População rural

Numerical simulation of a liquid cyclotron target

One of the most common PET isotopes, 18F, is mainly produced in liquid targets. The production yield depends linearly on the proton beam current used. However, for a fixed proton-beam energy increasing the current of the proton beam results in depositing increasing amounts of heat into the enclosed water target chamber and eventually in its failure. Hence, understanding the thermodynamics of a water target chamber could lead to a target optimization, removing the maximum amount of heat to balance the pressure, increasing the yield and guaranteeing the stability and durability of the system. Work in modeling the thermodynamic processes in a liquid target has also been per-formed by other groups [1-3] and others such as Steinbach [4] have performed analytical analyses of thermal behavior