965 resultados para CNPQ::ENGENHARIAS::ENGENHARIA MECANICA::PROCESSOS DE FABRICACAO
Resumo:
Automatic detection of blood components is an important topic in the field of hematology. The segmentation is an important stage because it allows components to be grouped into common areas and processed separately and leukocyte differential classification enables them to be analyzed separately. With the auto-segmentation and differential classification, this work is contributing to the analysis process of blood components by providing tools that reduce the manual labor and increasing its accuracy and efficiency. Using techniques of digital image processing associated with a generic and automatic fuzzy approach, this work proposes two Fuzzy Inference Systems, defined as I and II, for autosegmentation of blood components and leukocyte differential classification, respectively, in microscopic images smears. Using the Fuzzy Inference System I, the proposed technique performs the segmentation of the image in four regions: the leukocyte’s nucleus and cytoplasm, erythrocyte and plasma area and using the Fuzzy Inference System II and the segmented leukocyte (nucleus and cytoplasm) classify them differentially in five types: basophils, eosinophils, lymphocytes, monocytes and neutrophils. Were used for testing 530 images containing microscopic samples of blood smears with different methods. The images were processed and its accuracy indices and Gold Standards were calculated and compared with the manual results and other results found at literature for the same problems. Regarding segmentation, a technique developed showed percentages of accuracy of 97.31% for leukocytes, 95.39% to erythrocytes and 95.06% for blood plasma. As for the differential classification, the percentage varied between 92.98% and 98.39% for the different leukocyte types. In addition to promoting auto-segmentation and differential classification, the proposed technique also contributes to the definition of new descriptors and the construction of an image database using various processes hematological staining
Resumo:
A major and growing problems faced by modern society is the high production of waste and related effects they produce, such as environmental degradation and pollution of various ecosystems, with direct effects on quality of life. The thermal treatment technologies have been widely used in the treatment of these wastes and thermal plasma is gaining importance in processing blanketing. This work is focused on developing an optimized system of supervision and control applied to a processing plant and petrochemical waste effluents using thermal plasma. The system is basically composed of a inductive plasma torch reactors washing system / exhaust gases and RF power used to generate plasma. The process of supervision and control of the plant is of paramount importance in the development of the ultimate goal. For this reason, various subsidies were created in the search for greater efficiency in the process, generating events, graphics / distribution and storage of data for each subsystem of the plant, process execution, control and 3D visualization of each subsystem of the plant between others. A communication platform between the virtual 3D plant architecture and a real control structure (hardware) was created. The goal is to use the concepts of mixed reality and develop strategies for different types of controls that allow manipulating 3D plant without restrictions and schedules, optimize the actual process. Studies have shown that one of the best ways to implement the control of generation inductively coupled plasma techniques is to use intelligent control, both for their efficiency in the results is low for its implementation, without requiring a specific model. The control strategy using Fuzzy Logic (Fuzzy-PI) was developed and implemented, and the results showed satisfactory condition on response time and viability
Resumo:
Innovation has become an increasingly central issue of great reputation, not only in literature but also in management practices, becoming a strategic issue for managers of organizations. Allied to this, there is a high degree of competitiveness on the market, which contributes to the complexity of decision making, since managers need to maintain a continuous cycle of renewal processes and products. Thus, market pressures for new alternatives encourage innovation within organizations as a foundation for culture change in pursuit of survival and increased competitiveness, making it essential to know the factors that promote the advancement of organizational environments targeted innovation. Confirming this view, Bouchikhi and Kimberly (2001) symbolically expressed the idea with two statements: (1) companies need to innovate to survive, otherwise they die; and (2) the wide recognition of this need, as well as the difficulty to encourage and support innovation and entrepreneurship in business, has generated a mini-industry research and consulting in management focused on these topics. This study is characterized as descriptive with qualitative and quantitative methods. As for the planning of the research, it was decided to bibliographical research and the case study. The research, developed here, is meant to examine the organizational environment of a laboratory focused on technological innovation in health, which is a reference in research and technology of Rio Grande do Norte, and ensure that it presents opportunities to develop innovations. Therefore, the technologies developed by the Laboratório de Inovação Tecnológica em Saúde - LAIS/UFRN were mapped and then a questionnaire with the stakeholders of LAIS/UFRN was applied. This questionnaire is closed and Likert scale. As a result, it follows that the dimensions 1, 6, 7 and 8 are the most influential to form an innovative environment at LAIS.
Resumo:
Considered as one of the oldest activities done by men, the civil construction represents one of the most important sectors for the economic growth of a country, in spite of the low results of growth in the past few years and also in the current year. To make this industry grow, even with an unfavourable economic scenario, it is necessary to implement an effective planning in its activities. This is one of the most important concepts brought by the Lean Construction philosophy, which had its origin through the adaptation of the concepts established by the Toyota Production System (TPS) or Lean Production. By having as a scenario the city of Natal\RN, the main goal of this dissertation consists in investigating how the 11 principles of the lean construction influenced the schedule of a construction field that started to implement its lean concepts. As a methodology, it was used the case study of a big enterprise located in Natal (RN). During the execution of the method, documents related to the short-term, midterm and long-term planning were analysed , aiming to describe its planning process; it was also described the factors that caused the delays at the enterprises’ field ;in addition, a comparison was made between the results obtained at the case study and the ones presented at the literature; in the end, the actions were listed by the company, which had the purpose to solve the main causes of delays, verifying if they were linked to the lean construction principles. This research finds its reason of existence in the relevance of its theme at the nowadays reality of the construction industry, since the principles of the lean construction uphold the reduction of processes that are useless, diminishing wastes as well as costs in construction. The relevance is perceived for the academy, in terms of the possibility to discuss if the concepts established by the lean production are being adapted to the civil construction sector and how this adaptation is influencing at the buildings planning project. Economic importance, because with the reduction of the wastes and costs, the companies may reduce the building´s value into a more accessible value, even with the sector´s lower growth. And social significance, because lean construction gives a better participation of the labour at the planning activity. Among the main results, the high frequency of planning errors stands out, mainly the programming deviations and not the task programming, as well as the execution errors, low productivity and activities executed by the workers. Amongst the 11 principles of lean construction, only five were related with the 12 actions analysed by the author. From the 12 actions, four were completely cohesive to one or more from these five principles. Some improvement proposals were also highlighted and established by the research.
Resumo:
Tailings dams are structures that aims to retain the solid waste and water from mining processes. Its analysis and planning begins with searching of location for deployment, step on which to bind all kinds of variables that directly or indirectly influence the work, such as geological, hydrological, tectonic, topographic, geotechnical, environmental, social characteristics, evaluation security risks, among others. Thus, this paper aims to present a study on the most appropriate and secure type of busbar to design a layout structure of iron ore tailings, taking into account all the above mentioned variables. The case study involves the assessment of sites for location of dams of tailings disposal beneficiation of iron mine to be built in Bonito, in the municipality of Jucurutu in Seridó Potiguar. For site selection among alternatives, various aspects of the current state of the art were considered, one that causes the least environmental impact, low cost investment, adding value to the product and especially the safety of the implanted structure mitigates the concern about induced earthquakes as a result of liquefaction wastes somatized by dams in the region, as the tilling of Mina Bonito is located practically in the hydraulic basin dam Armando Ribeiro in environmental protection (APA). The methodology compares induced by dams in the semiarid region with the characteristics of the waste disposal and sterile seismicity, taking into account the enhancement of liquefaction by the action of seismicity in the Mina Bonito region. With the fulcrum in the methodology, we indicated the best busbar type for disposal of tailings from iron ore or combination of them, to be designed and built in semiarid particularly for Mina Bonito. Also presents a number of possible uses for the tailings and in engineering activities, which may cause processing to the common good.
Resumo:
Actually, Brazil is one of the larger fruit producer worldwide, with most of its production being consumed in nature way or either as juice or pulp. It is important to highlig ht in the fruit productive chain there are a lot lose due mainly to climate reasons, as well as storage, transportation, season, market, etc. It is known that in the pulp and fruit processing industy a yield of 50% (in mass) is usually obtained, with the other part discarded as waste. However, since most this waste has a high nutrient content it can be used to generate added - value products. In this case, drying plays an important role as an alternative process in order to improve these wastes generated by the fruit industry. However, despite the advantage of using this technique in order to improve such wastes, issues as a higher power demand as well as the thermal efficiency limitation should be addressed. Therefore, the control of the main variables in t his drying process is quite important in order to obtain operational conditions to produce a final product with the target specification as well as with a lower power cost. M athematical models can be applied to this process as a tool in order to optimize t he best conditions. The main aim of this work was to evaluate the drying behaviour of a guava industrial pulp waste using a batch system with a convective - tray dryer both experimentally and using mathematical modeling. In the experimental study , the dryin g carried out using a group of trays as well as the power consume were assayed as response to the effects of operational conditions (temperature, drying air flow rate and solid mass). Obtained results allowed observing the most significant variables in the process. On the other hand, the phenomenological mathematical model was validated and allowed to follow the moisture profile as well as the temperature in the solid and gas phases in every tray. Simulation results showed the most favorable procedure to o btain the minimum processing time as well as the lower power demand.
Resumo:
Given the growth demand for air transport allied to the need of adequacy of the infrastructure of the airports the need arises for the elaboration and Project Deployment enhancements to to the administrative management with efficiency and effectiveness of processes. The present dissertation aims to develop an organizational and operational proposal to management improvement projects an airport midsize business. The state of art literature contemplated the following topics: project management, project office; improvement approaches; improvement projects and technical and support improvement projects and project management tools. The research method is characterized as a case study of a qualitative nature. The validation of the proposal was carried out through a focus group with the participation twelve representatives of the administrative areas of an airport-sized Brazilian midfielder with the objective of validate the proposed organizational structure and operational procedures and to identify the barriers to implementation of the proposal. The result of the work presents an proposed considering the integration of the project office with the organizational structure of the administration, the conception of the project office, operating procedures and the directives for implementation
Resumo:
Currently the market requires increasingly pure oil derivatives and, with that, comes the need for new methods for obtaining those products that are more efficient and economically viable. Considering the removal of sulfur from diesel, most refineries uses catalytic hydrogenation process, the hydrodesulfurization. These processes needs high energy content and high cost of production and has low efficiency in removing sulfur at low concentrations (below 500 ppm). The adsorption presents itself as an efficient and economically viable alternative in relation to the techniques currently used. With that, the main purpose of this work is to develop and optimize the obtaining of new adsorbents based on diatomite, modified with two non ionic surfactants microemulsions, adding efficiency to the material, to its application on removal of sulfur present in commercial diesel. Analyses were undertaken of scanning electron microscopy (SEM), x-ray diffraction (XRD), x-ray fluorescence (XRF), thermogravimetry (TG) and N2 adsorption (BET) for characterization of new materials obtained. The variables used for diatomite modification were: microemulsion points for each surfactant (RNX 95 and UNTL 90), microemulsion aqueous phase through the use or non-use of salts (CaCl2 and BaCl2), the contact time during the modification and the contact form. The study of adsorption capacity of materials obtained was performed using a statistical modeling to evaluate the influence of salt concentration in the aqueous phase (20 ppm to 1500 ppm), finite bath temperature (25 to 60° C) and the concentration of sulphur in diesel. It was observed that the temperature and the concentration of sulphur (300 to 1100 ppm) were the most significant parameters, in which increasing their values increase the ability of modified clay to adsorb the sulphur in diesel fuel. Adsorption capacity increased from 0.43 to mg/g 1.34 mg/g with microemulsion point optimization and with the addition of salts.
Resumo:
The textile sector is one of the main contributors to the generation of industrial wastewaters due to the use of large volumes of water, which has a high organic load content. In these, it is observed to the presence of dyes, surfactants, starch, alcohols, acetic acid and other constituents, from the various processing steps of the textiles. Hence, the treatment of textile wastewater becomes fundamental before releasing it into water bodies, where they can cause disastrous physical-chemical changes for the environment. Surfactants are substances widely used in separation processes and their use for treating textile wastewaters was evaluated in this research by applying the cloud point extraction and the ionic flocculation. In the cloud point extraction was used as surfactant nonylphenol with 9.5 ethoxylation degree to remove reactive dye. The process evaluation was performed in terms of temperature, surfactant and dye concentrations. The dye removal reached 91%. The ionic flocculation occurs due to the presence of calcium, which reacts with anionic surfactant to form insoluble surfactants capable of attracting the organic matter by adsorption. In this work the ionic flocculation using base soap was applied to the treatment of synthetic wastewater containing dyes belonging to three classes: direct, reactive, and disperse. It was evaluated by the influence of the following parameters: surfactant and electrolyte concentrations, stirring speed, equilibrium time, temperature, and pH. The flocculation of the surfactant was carried out in two ways: forming the floc in the effluent itself and forming the floc before mixing it to the effluent. Removal of reactive and direct dye, when the floc is formed into textile effluent was 97% and 87%, respectively. In the case where the floc is formed prior to adding it to the effluent, the removal to direct and disperse dye reached 92% and 87%, respectively. These results show the efficience of the evaluated processes for dye removal from textile wastewaters.
Resumo:
Valve stiction, or static friction, in control loops is a common problem in modern industrial processes. Recently, many studies have been developed to understand, reproduce and detect such problem, but quantification still remains a challenge. Since the valve position (mv) is normally unknown in an industrial process, the main challenge is to diagnose stiction knowing only the output signals of the process (pv) and the control signal (op). This paper presents an Artificial Neural Network approach in order to detect and quantify the amount of static friction using only the pv and op information. Different methods for preprocessing the training set of the neural network are presented. Those methods are based on the calculation of centroid and Fourier Transform. The proposal is validated using a simulated process and the results show a satisfactory measurement of stiction.
Resumo:
The heavy part of the oil can be used for numerous purposes, e.g. to obtain lubricating oils. In this context, many researchers have been studying alternatives such separation of crude oil components, among which may be mentioned molecular distillation. Molecular distillation is a forced evaporation technique different from other conventional processes in the literature. This process can be classified as a special distillation case under high vacuum with pressures that reach extremely low ranges of the order of 0.1 Pascal. The evaporation and condensation surfaces must have a distance from each other of the magnitude order of mean free path of the evaporated molecules, that is, molecules evaporated easily reach the condenser, because they find a route without obstacles, what is desirable. Thus, the main contribution of this work is the simulation of the falling-film molecular distillation for crude oil mixtures. The crude oil was characterized using UniSim® Design and R430 Aspen HYSYS® V8.5. The results of this characterization were performed in spreadsheets of Microsoft® Excel®, calculations of the physicochemical properties of the waste of an oil sample, i.e., thermodynamic and transport. Based on this estimated properties and boundary conditions suggested by the literature, equations of temperature and concentration profiles were resolved through the implicit finite difference method using the programming language Visual Basic® (VBA) for Excel®. The result of the temperature profile showed consistent with the reproduced by literature, having in their initial values a slight distortion as a result of the nature of the studied oil is lighter than the literature, since the results of the concentration profiles were effective allowing realize that the concentration of the more volatile decreases and of the less volatile increases due to the length of the evaporator. According to the transport phenomena present in the process, the velocity profile tends to increase to a peak and then decreases, and the film thickness decreases, both as a function of the evaporator length. It is concluded that the simulation code in Visual Basic® language (VBA) is a final product of the work that allows application to molecular distillation of petroleum and other similar mixtures.
Resumo:
This dissertation introduces a study that aims to analyze the simulated training of emergency teams and proposes recommendations for the current training system in order to improve the collective skills and resilience of these teams when facing possible critical situations, triggered by possible accident occurrences during aerospace vehicle launching operations in the Barreira do Inferno Launch Center in Parnamirim / RN. This is a field, exploratory, descriptive, explanatory, and a case study with a qualitative approach. Therefore, we adopted the ergonomics approach, using the situated method of ergonomic work analysis (AET), combining observational and interactive methods. The relevance of this research is characterized by the contributions to minimize the human and material hazzards resulting from possible accidents in these operations, the scientific contribution of the AET for simulated emergency training analysis in the launching operations of aerospace vehicles - which are complex and involve risk of accidents - and consequently, the scientific contribution to the current process of recovering the Brazilian Space Program. The survey results point to problems of various kinds in the current simulated training system which compromise the safety of the operations. These problems are grouped into four categories: technological, organizational, team training and from the activity itself, regarding more specifically communication and cooperation (among the team members and these ones with other sectors involved in the launching operation) and regarding the coordination of actions. We propose: a) a new training model, from the creation and application of scenarios based on postulated abnormalities, which could simulate real critical situations, in order to train and improve the skills of the emergency response teams especially in terms of communication, coordination and cooperation; b) restructuring and reorganizing the current training system, based on the formal establishment of a managing staff, on the clear division of responsibilities, on the standardization of processes, on the production of management indicators, on the continuous monitoring, on the feedback from trainees about the quality of the training and on the continuing and frequent training of emergency teams.
Resumo:
One of several techniques applied to production processes oil is the artificial lift, using equipment in order to reduce the bottom hole pressure, providing a pressure differential, resulting in a flow increase. The choice of the artificial lift method depends on a detailed analysis of the some factors, such as initial costs of installation, maintenance, and the existing conditions in the producing field. The Electrical Submersible Pumping method (ESP) appears to be quite efficient when the objective is to produce high liquid flow rates in both onshore and offshore environments, in adverse conditions of temperature and in the presence of viscous fluids. By definition, ESP is a method of artificial lift in which a subsurface electric motor transforms electrical into mechanical energy to trigger a centrifugal pump of multiple stages, composed of a rotating impeller (rotor) and a stationary diffuser (stator). The pump converts the mechanical energy of the engine into kinetic energy in the form of velocity, which pushes the fluid to the surface. The objective of this work is to implement the optimization method of the flexible polyhedron, known as Modified Simplex Method (MSM) applied to the study of the influence of the modification of the input and output parameters of the centrifugal pump impeller in the channel of a system ESP. In the use of the optimization method by changing the angular parameters of the pump, the resultant data applied to the simulations allowed to obtain optimized values of the Head (lift height), lossless efficiency and the power with differentiated results.
Resumo:
The Nb-Cu pseudoalloys present themselves as potential substitutes for the alloys from a well known system and already commercially applied, as the W-Cu alloys, used in applications such as heat sinks, electrical contacts and coils for the generation of high magnetic fields. Because it is an immiscible system, where there is mutual insolubility and low wettability of the liquid Cu on the Nb surface, the processing route used in this work was the Powder Metallurgy. Two Nb alloys were used, with additions of 10% and 20% in weight of Cu, and times of 20, 30 and 40 hours for the high energy milling of the starting powders. The milling evolution of the powders is presented through the characterization techniques, such as the LASER diffraction for particle size, XRD, SEM, EDS, DSC, dilatometry, TEM and chemical analysis. After the milling, portions of the loads were submitted to the annealing heat treatment. The process used for the samples consolidation was the hot pressing, which has been applied both on some milled powders samples, as on the annealed powders. Subsequent heat treatments were performed in the samples at temperatures of 1000ºC (solid phase) and 1100ºC (in the Cu liquid phase). All sets of consolidated samples, and also the two sets of the heat treated, were analyzed by XRD, SEM, EDS, density and Vickers microhardness. Moreover, other Nb powder samples with 10% and 20% in weight of Cu obtained by simple mechanical mixing, were consolidated, thermally treated and characterized with the same techniques applied to the others, and the results were compared among themselves. Despite the difficulty of consolidation and densification of the two pseudoalloys of the Nb-Cu system of this study, on the route that passes through the HEM, samples were obtained with densities around 90% of the theoretical density. And, on the processing route of which were only mixed, the values reached up to 97%. Therefore, in this work are also emphasized the processes that made possible these results.
Resumo:
Camu-camu (Myrciaria dubia H.B.K. (McVaugh)) is a native Amazon fruit, recognized worldwide as one of the main natural sources of ascorbic acid. Due to its great acidity, this fruit is generally consumed after processing into juice or as ingredient in food preparations. As a co-product of the camu-camu processing, a significant amount of agroindustrial residue is generated. Despite the studies showing the bioactive value and biological potential of the fruit, few studies have approached the possible processing techniques, transformation and preservation of camu-camu fruits and its agroindustrial pomace. Therefore, the present work has the objective of evaluating two different drying processes applied to camu-camu pomace (peel and seeds with residual pulp), freeze drying and hot air drying, in order to obtain a functional fruit product. This thesis was divided into three stages: the first one shows the studies related to the freeze drying and hot air drying, where we demonstrated the impact of the selected drying techniques on the bioactive components of camu-camu, taking the fresh pomace as the control group. Among the investigated conditions, the groups obtained at 50ºC and 4 m/s (SC50) and 80ºC and 6 m/s (SC80) were selected as for further studies, based on their ascorbic acid final content and Folin-Ciocalteau reducing capacity. In addition to SC50 and SC80, the fresh pomace (RF) and freeze dried (RL) samples were also evaluated in these further stages of the research. Overall, the results show higher bioactive concentration in the RF samples, followed by RL, SC50 and SC80. On the second step of the research, the antioxidant, antimicrobial and antienzymatic activities were evaluated and the same tendency was observed. It was also reported, for the first time in the literature, the presence of syringic acid in dried camu-camu pomace. In the third and final stage of the research, it was investigated the effect of dried camu-camu on aging and neuroprotective disorders, using the in vivo model C.elegans. It was observed that camu-camu extracts were able to modulate important signaling genes relevant to thermal and oxidative stresses (p < 0.05). The polar acid, polar basic and polar neutral fractions obtained from the low molecular extracts of SC50 were able to extend the lifespan of wild type N2 C. elegans in 20% and 13% (p < 0.001). Results also showed that the paralysis induced by the β1-42 amyloid was significantly (p < 0.0001) retarded in CL4176 worms. Similarly, the camu-camu extracts attenuated the dopaminergic induction associated to Parkinson’s disease. Finally, a global analysis of the data presented here reveal that the camu-camu pomace, a co-product obtained from the industrial processing of a native Brazilian fruit, is a relevant natural source of health relevant compounds. This thesis, shows for the first time, the multifunctionality of camu-camu pomace, a natural resource still underexploited for scientific, commercial and technological purposes.