A simulação de Monte Carlo como instrumento fundamental para a análise de viabilidade econômica: a implementação de uma fundição de ferro em uma empresa metalúrgica

In uncertainly economic scenarios, an economic feasibility analysis must be done to accept a project based on investment criteria, such as NPV and IRR, mainly because the shareholders tend to invest their budget in a project if it has a great chance to return their investments. The studied company outsources all of its foundry services, what makes it very dependent of its suppliers, because the products have a lower quality level, long delivery periods and high prices. Therefore, this work will analyze the project of building an iron-casting foundry to decrease the dependence of its suppliers. In order to develop this research, all needed data related to the construction of the foundry and sales were collected to create deterministic and probabilistic (Monte Carlo Simulation) cash flows using MsExcel® and Oracle's Crystal Ball® software. As a result, the project was found to be risky by the NPV and IRR in the case of this new production line supplying only the internal needs. However, when the company offers its services to the foundry market, the project turns to be feasible

Simulação do tempo de descarga de caminhões graneleiros em uma estação de transbordo de carga em Porto Murtinho, MS

In the current decade, inter modal transport is widely discussed. In Brazil road transport is used in excess whereas there could be more focus and investment towards water transport. Water transport presents many benefits like being low cost and low maintenance. Sea and river ports today aren't capable of supporting Brazil's transport needs. Therefore, with this obstacle, this paper consists of an attempt of modeling and simulation of the process of unloading grain cargo from trucks, through simulation with ProModel software, to verify the necessity of installing more tumblers at the cargo unloading station in Porto Murtinho, MS

Uma discussão sobre o ensino da estatística para os estudantes de graduação na França, no Brasil, e nos Estados Unidos

Today statistics are one of the most important bases of the engineer formation. Statistics are used indirectly every day for engineers in a large panel of sectors like construction, mechanical engineering, biological engineering, electrical engineering, computer science etc. The main goal of this report is to compare different ways the engineers of tomorrow are formed in order to show which engineering is the best practice. The comparison will be done on different universities in France, Brazil and the US on Mechanical, Civil, Electrical and Production branches. We will compare the amount of courses required, the degree of knowledge needed and the mains subjects

Determinação de manganêsem águas no entorno de minerações de urânio

The studies of this work aimed to determine the labile fractions of manganese (Mn) in natural and drainage water samples collected around the Osamu Utsumi uranium mine, located in the municipality of Caldas, south-central region of Poços de Caldas- MG, using the technique of diffusion gradient in thin films (DGT). The DGT devices were mounted with Chelex-100 resin, polyacrylamide-agarose hydrogel (conventional porosity) and cellulose acetate membrane. The device were deployed up to 48 hours in six water samples collected from different areas around the uranium mine (075, 076, 022-E, 025-E, 014, and 041). The DGT devices immersed in each sample were gradually removed after 4, 8, 12, 24 and 48 hours. The pH of the samples ranged from 3.0 to 10.5, which influenced the lability and the sampling of the analyte by the Chelex-100 resin. The results showed a linear relationship between accumulated mass and sampling time (immersion curve) for samples 014 and 025-E (pH between 6 and 8) suggesting the ability of the DGT technique for sampling the analyte. The results obtained for samples 075 and 076 (pH<5) and samples 041 and 022-E (pH around 10) were characterized by nonlinear relationships. The values obtained by DGT were compared with Solid Phase Extraction (SPE) technique using Chelex-100. For samples 014 and 025-E, there was a good agreement between the results obtained by both techniques

Estudo de placas elásticas pelo metodo dos elementos de contorno

Este trabajo tiene como objetivo principal oferecer una herramienta alternativa para la resolución de placas finas, presentes en edifícios, relacionadas con los métodos de cálculo adquiridos durante la universidad, calculo a través de tablas con pocas condiciones de controno. El método utilizado es el Método de los elementos de contorno que discretiza la placa en partes finitas, aproximando los resultados obtenidos a valores reales. En este trabajo se ha utilizado el programa de ordenador Placas2.for (TAGUTI,Y. 2010) basado en el Método de los elementos de contorno para la resolución de las placas finas con varias condiciones de contorno geométricas y de cargas

O efeito da autocorrelação no desempenho dos gráficos de X e R e dos gráficos de X e S²

Control charts are very important tools in statistical quality control of industrial processes and its use started last century. Since its development, the charts have always been attributed to independent processes, i.e. without any correlation between samples. But nowadays, with the high level of automation in the industrial environment, it is noticeable the autocorrelation factor between samples. The main Xcharts used in monitoring quality characteristics represented by continuous variables are the mean (X ), amplitude (R) and variance (S²). Therefore, this work aims to analyze the performance of X and R charts and in of X and S² charts with different sample sizes (4 and 5) for monitoring autocorrelated processes. Through computer simulations using the Fortran software and the use of mathematical expressions was possible to obtain data and performance analysis of the detection power charts for independent observations and for autocorrelated observations according to the model AR (1). The results show that the effect of autocorrelation reduces the ability of monitoring the control charts and that, the greater this effect, the slower the chart becomes in misfits signaling

Radioterapia em câncer de mama: importância da determinação da curva de isodose

The study analyzed contours of the thoracic region of patients undergoing radiotherapy of breast tumors in Hospital Manuel de Abreu of Bauru (institution 1) and the Hospital da Faculdade de Medicina of Botucatu (Institution 2). Were prepared isodose curves corresponding to the contours of the patient, which were presented for radiotherapists doctors both hospital services that enabled the choice of the curve isodose that provides the best distribution of radiation dose in the irradiated volume. Some boundaries were digitized in one institution and sent for preparation of isodose lines in the institution 2, both curves plotted in each of the institutions and for the same contour, were compared, showing that the methodology of Curves of distance is feasible and reliable, while optimizing the routine procedures regarding the handling of isodose plans provided by different radiation equipment. It compares the calculation of the exposure time determined using the isodose curve selected by calculating the value obtained considering the PDP at the point of the middle line of separation between the internal and external fields, the difference between the two methods for determining exposure time was around 2.4%. A study on the angle of the radiation beam at the input field (region breast-air) was conducted showing that, once known a tangent angle of the input beam, one can estimate the angle of the wedge filter used in some procedures for uniformity of dose within the irradiated volume compensation and the lack of tissue in the treatment volume. A comparative study between the isodose curves produced manually with the curves obtained in a two-dimensional computer system, the computer system showed that provides further information regarding the dose gradient within the irradiated volume, in addition to reducing the time spent in preparing the curves isodose

Análise da estabilidade do movimento rotacional de satélites artificiais com quatérnions e sob a influência de torques externos

The aim of this work is to analyze the stability of the rotational motion’s artificial satellite using the Routh Hurwitz Algorithm (CRH) and the quaternions to describe the satellite’s attitude. This algorithm allows the investigation of the stability of the motion using the coefficients of the characteristic equation associated with the equation of the rotational motion in the linear form. The equations of the rotational motion are given by the four cinematic equations for the quaternion and the three equations of Euler for the spin velocity’s components. In the Euler equations are included the components of the gravity gradient torque (TGG) and the solar radiation torque (TRS). The TGG is generated by the difference of the Earth gravity force direction and intensity actuating on each satellite mass element and it depends on the mass distribution and the form of the satellite. The TRS is created by changing of the linear momentum, which happens due to the interactions of solar photons with the satellite surface. The equilibrium points are gotten by the equation of rotational motion and the CRH is applied in the linear form of these equations. Simulations are developed for small and medium satellites, but the gotten equilibrium points are not stable by CRH. However, when some of the eigenvalues of the characteristic equation are analyzed, it is found some equilibrium points which can be pointed out as stables for an interval of the time, due to small magnitude of the real part of these eigenvalue

Influência do uso de malhas de sombreamento azul, vermelha e preta no desenvolvimento inicial do pepino Taiko

Cucumber (Cucumis sativus L.) is a plant of the Cucurbitaceae family of great commercial importance and their culture is widespread throughout the country. The production of vegetables, high-quality care begins with training ranging from seedlings and shading techniques have an important role in creating environments more conducive to the production of seedlings and many researchers and producers of seedlings have opted for the use of color shading screens, making this way, the wavelength and the amount of incident energy are changed in favor of the plants. Work will be performed at the Department of Forest Sciences, Faculty of Agricultural Sciences, Universidade Estadual Paulista (UNESP), Botucatu campus. The statistical design will be in three blocks, each containing 100 plots of each treatment (seedlings covered with blue screen, red and black). Evaluations of dry mass and height will be made at 7, 14, 21 and 28 days after emergence, and 5 will be selected seedlings of each treatment. At 14 and 28 DAE was measured, and SPAD chlorophyll content at 30 DAE, was evaluated by measuring gas exchange in the second pair of leaves, fully expanded for each plant, which was put in a chamber controlled with infrared gas analyzer (IRGA LI 6400, Licor) to perform measurements of photosynthesis. Treatment with black shading showed statistically better results for total dry matter, plant height, SPAD chlorophyll content and net assimilation of CO2, showing a better quality seedlings and its use is recommended in the cultivation of cucumber Taiko

Redução do tempo de ciclo baseado na produção enxuta em uma rémontagem de tubos de freios e combustível

In today's competitive environment of automakers, it is essential to obtain the highest efficiency of the production process. This paper presents a study in a pre-assembly of brake pipes and fuel of a vehicle where the value stream maps and information (VSM – Value Stream Mapping) were designed in order to improve the process by reducing the Lead Time Production of a product, reducing waste and decrease time between processes. This work can be divided into three stages, the first building the VSM of the initial state, the second VSM of the proposed state and finally the VSM than was actually performed and to present the gains were achieved effectively. The proposed VSM would lead to a gain of 54% in lead time and 61% in processing time, since the VSM implemented had gains of 47% in lead time and 48% in processing time even without major investments as originally proposed. Concluding that even without big investment, using the techniques of lean manufacturing is possible to achieve high levels of process efficiency

Resposta da comunidade de formigas ao efeito de borda em paisagens de Cerrado

Uma das principais alterações ambientais decorrentes da ação antrópica é o efeito de borda, consequência direta da fragmentação, que altera condições microclimáticas nas bordas dos fragmentos. Este processo afeta a biodiversidade, interferindo na dinâmica das comunidades, tanto vegetais, quanto animais, alterando a composição e a estrutura das comunidades. Através da utilização de bioindicadores é possível compreender como alterações nos hábitats interferem nas comunidades locais, ou em processos ecológicos essenciais para a manutenção do ecossistema e da biodiversidade local ou regional. Devido à grande riqueza, abundância e importância em diversos processos ecológicos, como por exemplo, dispersão de sementes e ciclagem de nutrientes, as formigas têm sido utilizadas como indicadores ambientais. Os objetivos deste trabalho foram avaliar como as comunidades de formigas de fragmentos de cerrado respondem ao efeito de borda, especificamente se essa resposta ocorre de forma gradiente ou hábitat-matriz (formigas não estão presentes na borda). Também foi analisado se o tipo de matriz adjacente influencia nessas respostas observadas em 15 paisagens de cerrado circundadas por matrizes de pasto, cana-de-açúcar e eucalipto onde se utilizou armadilhas de queda ao longo de transectos posicionados tanto dentro como fora dos fragmentos. Para a riqueza total de formigas o modelo hábitat-matriz com interferência da matriz foi o que melhor explicou a distribuição. Os modelos que melhor explicaram a riqueza e abundância dos grupos funcionais variaram consideravelmente, o que evidencia a importância de buscar modelos mais complexos (modelo gradiente) que expliquem tanto as respostas mais simples (hábitat-matriz)como as mais multíplices. As comunidades analisadas apresentam diferentes funções dentro do hábitat e das matrizes, dessa forma participam de vários processos ecológicos sendo assim bons indicadores...

Estudo do metamorfismo de rochas de alto grau do grupo Araxá na região de São Sebastião do Paraíso - MG

This study focuses on metasedimentary rocks from the Passos Nappe in São Sebastião do Paraíso, southern Minas Gerais, Brazil. These rocks belong to the Internal Domain (Araxa Group) of the Southern Brasilia Belt, a Neproterozoic orogenic belt associated to the formation of the Gondwana Supercontinent. Rocks from the studied area are characterized by an inverted metamorphic gradient. Previously calculated metamorphic conditions show an increasing from geenschist facies at the base (450°C, 6 kbar), to upper amphibolite facies (750°C, 11 Kbar) at the top of the sequence. However, most of these estimates are based on Fe-Mg exchange thermometers and peak temperatures may be underestimated due to Fe-Mg exchange from cooling after peak metamorphism. In this study, we present new PT results for these rocks, based on metamorphic mineral assemblage LA-ICP-MS analyses. In the studied area, rocks from the top of the sequence have a typical granulite facies mineral assemblage: Grt+Ky+Kfs+/-Pl+liq. These rocks lack muscovite and have only minor amounts of Ti-rich, dark brown biotite. In a simplified NaKFMASH system the stability field for this mineral assemblage is bounded by the reactions Sil = Ky on the low pressure side, Ms+Ab = Ky+Kfs+liq on the low temperature side and for high-Mg bulk compositions Bt + Grt = Opx + Ky + liq on the high-temperature side. Minimum temperatures (considering post-peak reequilibration) of ca. 750°C are obtained by Fe/(Fe+Mg) values of 0.7 in garnets from a Grt+Ky+Kfs bearing sample. LA-ICP-MS results obtained for three samples show that rutiles included in garnets have up to 1847 ppm of Zr, which would translate into temperatures up to 830°C for a pressure between 12 to 15 kbar. Also for retroeclogite sample, the results indicate the contents of Zr in the garnet 537 ppm at a temperature of 708 ° C. It is noteworthy that several occurrences of retroeclogites occur in the upper part of the sequence and pressures...

Análise da viabilidade de simulações com feixes de prótons de 100, 150, 200 e 250 MeV em alvos heterogêneos

In the recent years, the use of proton beams in radiotherapy has been an outstanding progress (SMITH, 2006). Up to now, computed tomography (CT) is a prerequisite for treatment planning in this kind of therapy because it provides the electron density distribution required for calculation of dose and the interval of doses. However, the use of CT images for proton treatment planning ignores fundamental differences in physical interaction processes between photons and protons and is, therefore, potentially inaccurate (SADROZINSKI, 2004). Proton CT (pCT) can in principle directly measure the density distribution needed in a patient for the dose distribution (SCHULTE, et al, 2004). One important problem that should be solved is the implementation of image reconstruction algorithms. In this sense, it is necessary to know how the presence of materials with different density and composition interfere in the energy deposition by ionization and coulomb excitation, during its trajectory. The study was conducted in two stages, was used in both the program SRIM (The Stopping and Range of Ions in Matter) to perform simulations of the interaction of proton beams with pencil beam type. In the first step we used the energies in the range of 100-250 MeV (ZIEGLER, 1999). The targets were set to 50 mm in length for the beam of 100 MeV, due to its interaction with the target, and short-range, and 70 mm for 150, 200 and 250 MeV The target was composed of liquid water and a layer of 6 mm cortical bone (ICRP). It were made 9 simulations varying the position of the heterogeneity of 5 mm. In the second step the energy of 250 MeV was taken out from the simulations, due to its greater energy and less interaction. The targets were diminished to 50 mm thick to standardize the simulations. The layer of bone was divided into two equal parts and both were put in the ends of the target... (Complete abstract click electronic access below)

Ciclo PDCA e ferramentas da qualidade em operações e serviços de e-commerce

The market has forced companies to maintain high levels of control over their processes , ensuring a product or service quality to its customers . This study comes in the issuance and registration carried out in a company of e-commerce , which is showing problems with the values of weights and dimensions used in the cases cited . The need to eliminate wasteful spending freight caused by shipment of products weighing more than the reality, and to increase the reliability of the information used in the management of processes led to the planning of this project . This work focuses on the development of a PDCA cycle to work in the identification and correction of the causes of the problem , in order to neutralize the current complications and ensure that the problem does not appear again. To aid the mapping of the processes involved , identifying the causes of the problem and implementation of the proposed improvements were used quality tools such as flowcharts , Ishikawa diagrams , Pareto diagrams , and applied statistics

Influência da luz LED em culturas de células-tronco mesenquimais in-vitro

Stem cells are defined as cells capable of self-renewal and differentiation into specialized cells when submited to external signalings in the enviroment. Among adult stem cells, mesenchymal cells occupy an important position because they can differentiate into mesodermal cells such as osteoblasts, adipocytes and chondrocytes. Cell therapy consists in the use of mesenchymal stem cells (MSC) in the treatment of degenerative diseases and harmed tissue reconstruction. Due to the longstanding and costly procedure for cultivation of MSC, it was proposed the use of low power light sources, such as light emitting diodes (LED), to optimize these factors. Recent works have shown a series of results from the influence of LED light on biological tissues such as increased rate of cell proliferation, increased RNA, DNA and ATP synthesis rate. The purpose of this study is to compare the biomodulator effect of LED light set at wavelengths 630nm ± 10nm and 805nm ± 10nm on the mesenchymal stem cells proliferation. For this, the mesenchymal stem cells culture adopted the procedure used in the Departament of Animal Reproduction and Veterinary Radiology of the Faculty of Veterinary Medicine and Animal Sciences of Botucatu. MSC were obtained from an adult horse bone marrow, and isolated by density gradient separation, with the FICOLL reagent and by centrifugation. The pellet containing the stem cells was removed and these were placed in low glucose DMEM culture medium, containing 10% fetal calf serum and antibiotics. The material was observed daily by inverted microscopy for monitoring the progression of the cells and subsequently the amount of cells were counted in a Neubauer counting chamber. The amount of MSC was obtained by cell culture seeded in 24 wells culture plate and segregated into three distinct groups: Group 1 was irradiated with wavelength set at 630nm ± 10 nm, Group... (Complete abstract click electronic access below)