19 resultados para Théologie inductive

em Universidade Federal do Rio Grande do Norte(UFRN)


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This dissertation examines the organizational innovation as a nonlinear process, which occurs in a social and political context and, therefore, socially immersed. Examines the case of shrimp in the state of RN, starting from the following problem: although the norteriograndense shrimp occupies the largest producer of farmed shrimp from Brazil, has a series of bottlenecks concerning the generation of industry innovation, concerning the social relationships and policies between the various actors in the network, whether private or public, and its consequences in terms of opportunity and limits generated for the innovative dynamics. The objective of the research is to understand how the social embeddedness of political actors affects norteriograndense shrimp within the context of structural relations, the industry generation of innovation, throughout its technological trajectory . The approach of social embeddedness balances atomised perspectives, undersocialized and oversocialized, of economic action, considering both the human capacity to act as sources of constraint, whose mechanisms are analyzed the structural and political. In methodological terms this is a case study, analyzed from the research literature, documentary and experimental. Primary data were collected through semi-structured interviews and analyzed in depth by the technique of content analysis. Was adopted a longitudinal approach, seeking to understand the phenomenon from the perspective of the subjects, describing it in an inductive process of investigation. After characterizing the sector and defining their technological trajectory, the analysis of the results followed its four stages: (1) Introduction of Technology: 1973-1980, (2) Intensification of Research: 1981-1991, (3) Technological Adaptation, 1992 -2003, (4) Technological Crisis: 2004-2009. A cross-sectional analysis along the evolutionary trajectory revealed the character of structural changes and policies over time, and implications on the generating process of innovation. Note that, the technological limit to which the sector reached requires changes in technology standards, but is more likely that the potiguar shrimp is entering a new phase of his career in technology rather than a new technological paradigm

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The aim of this study was to learn about the social representations of the care provided by the Family Health Program (FHP) in the city of Natal, Brazil and determine how these representations guide the daily actions of doctors, dentists, nurses, nurse s assistants and oral health assistants during the work process. In this sense, we used the theoreticalmethodological approach to the Theory of Social Representations. For data collection, we used the following instruments: a two-part questionnaire, where the first part recorded sociodemographic data and the second part was adapted to the free word association technique (FWAT), which was applied to 90 professionals belonging to 18 FHP units. Interviews were also used as collection instruments. These were based on inductive stimuli and on direct observations of 30 of these professionals. After a superficial reading of the material, we constructed a corpus from which ten categories emerged. To analyze FWAT we used lexicographic analysis, combining frequency and the mean order of responses. The interviews and sociodemographic variables were analyzed using content analysis and descriptive statistical analysis, respectively. The study showed that the central nucleus of the social representation in question is composed of the elements attention, receptivity and love, revealing that the subjects have different understandings of the FHP care process and that the knowledge accumulated in this respect is supported by an approximate vision of the meaning of care. However, traditional elements with trivializing connotations about care predominate, which compromises the development of strategies to overcome traditional practices. In the set of analyses, we were able to capture the invariance of a contradiction: on one hand, professionals know and affirm the importance of providing care for FHP patients; on the other, the experience of daily practice translates into the negation of this concept. In this contradictory context, professionals build gradual and successive syntheses that allow them to act and affirm themselves by associating information from their academic formation, structured knowledge acquired in other experiences, values and symbols of their daily routine. Thus, they shape and reshape themselves, according to what is concretely and specifically required, at the same time both plural and multiple. The composition of the central nucleus indicates that any measure that intends to modify attitudes that is, the daily actions of FHP professionals with respect to care must take into account and give priority to the debate about the redefining of the semantic fields of the central nucleus (love/attention/receptivity and humanization), especially those of love and attention

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This study aims to identify the social representations built on senior care health workers of Primary Care. This is an exploratory research within the subsidized social representations held in 100 Basic Health Units in the city of João Pessoa-PB, with a sample of n= 204 workers of both sexes, who agreed to participate. To collect the data used to set an interview in two parts: the first looked at the Test of Free Association of Words using the inductive stimulus "senior care". The interviews were analyzed with the help of a software for quantitative analysis of textual data ALCESTE (version 2010). The results were interpreted from the theoretical framework of social representations. The study included 178 women (87.25%) and 26 men (12.75%), working in Family Health Units in the city of João Pessoa, the majority are aged between 40-49 years of age ( 28.92%), and have higher education with 81.86%. The results of Alceste link to the term inducer six (6) where the hierarchical classes representing senior care workers as synonymous with care and attention, showing situations neglect of the elderly, for that patience is required to promote the increase of disease prevention and living with the elderly to generate humanization in health services. It is considered that the social representations of health workers on assistance to the elderly may support modeling of strategic actions in health services with health promotion programs for large groups, able to modify practices and behavior in elder care and strengthening the policy was directed at the elderly

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This study aimed to analyze the social representations of Brazilian and Portuguese nurses on stress in the emergency service. A semi-structured interview and the free word association test, with "stress" as the inductive stimulus, were used as research instruments. Data were collected from 120 nurses, being 60 from an emergency hospital in the city of Natal, Brazil and 60 from an urgency hospital in the city of Aveiro, Portugal. Data from the word association test were analyzed with the EVOC 2002 program, after thematic categorical content analysis, enabling construction of a data bank. Data gathered from the interview were analyzed by ALCESTE 4.8 software. Nurse represent the stress in the urgency department as a generation of physical and mental detrition where adaptation is unsatisfactorily, resulting in the onset of fatigne, irritability, lack of concentration, lack of motivation, pessimism, impaired interpersonal relationship and low productivity. The solution is part of a complex whole, which demands an integrated way of acting that has demanded increasingly professional attitudes based on multidisciplinarity

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The thesis, prepared with basis on deductive reasoning (through the utilization of general concepts of the fundamental rights theory) and on inductive logic (by means of the consideration of particular situations in which the theme has been approached) deals with the criminal investigation and the prohibition of anonymity in the Brazilian law system. The state criminal investigation activity presents not only a substantial constitutional basis, due to the objective dimension of fundamental rights (which imposes an obligation to protect these essential values), but also a formal constitutional basis, arising from the administrative principles of rule of law, morality and efficiency, referred to in article 37 of the Constitution. The criminal investigation, however, is not an unlimited pursuit, being restrained by the duty to consider fundamental rights that oppose to its realization. One of the limits of the state investigation activity, in the Brazilian law system, is the prohibition of anonymity, referred to in article 5°, IV, of the Constitution. This prohibition is a direct constitutional restriction to the freedom of expression that aims to ensure the credibility of the diffusion of ideas and prevent the abusive exercise of this fundamental right, which could harm both persons and the state, with no possibility of punishment to the offending party. Generally, based on this prohibition, it is affirmed that a criminal investigation cannot begin and progress founded on anonymous communication of crimes. Informations about crimes to the investigative authorities require the correct identification of the stakeholders. Therefore, it is sustained that the prohibition of anonymity also comprehends the prohibition of utilization of pseudonyms and heteronyms. The main purpose of this essay is to recognize the limits and possibilities in starting and conducting criminal investigations based on communication of crimes made by unidentified persons, behind the veil of anonymity or hidden by pseudonyms or heteronyms. Although the prohibition of article 5°, IV, of the Constitution is not submitted to direct or indirect constitutional restrictions, this impediment can be object of mitigation in certain cases, in attention to the constitutional values that support state investigation. The pertinence analysis of the restrictions to the constitutional anonymity prohibition must consider the proportionality, integrated by the partial elements of adequacy, necessity and strict sense proportionality. The criminal investigation is a means to achieve a purpose, the protection of fundamental rights, because the disclosure of facts, through the investigatory activity, gives rise to the accomplishment of measures in order to prevent or punish the violations eventually verified. So, the start and the development of the state criminal investigation activity, based on a crime communication carried out by an unidentified person, will depend on the demonstration that the setting up and continuity of an investigation procedure, in each case, are an adequate, necessary and (in a strict sense) proportional means to the protection of fundamental rights

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The existence of inequalities among the Brazilian regions is an indeed fact along the country s history. Before this reality the constitutional legislator inserted into the Federal Constitution of 1988, as a purpose of the Federative Republic of Brazil, the reduction of regional inequalities. The development has also been included as a purpose from the State, because there is an straight relation with the reduction of regional inequalities. In both situations is searched the improvement of people s living conditions. . In pursuit of this achievement, the State must implement public policy, and, for this to happen, it needs the ingress of income inside of the public coffers and support of economic agents, therefore the importance of constitucionalization of the economic policy. The 1988 s Constitution adopted a rational capitalism regime consentaneous with current legal and social conceptions, that s why it enabled the State s intervention into economy to correct the so-called market failures or to make the established objectives fulfilled. About this last one, the intervention may happen by induction through the adoption of regulatory Standards of incentive or disincentive of economic activity. Among the possible inductive ways there are the tax assessments that aim to stimulate the economic agents behavior in view of finding that the development doesn t occur with the same intensity in all of the country s regions. Inside this context there are the Export Processing Zones (EPZs) which are special areas with different customs regime by the granting of benefits to the companies that are installed there. The EPZs have been used, by several countries, in order to develop certain regions, and economic indicators show that they promoted economic and social changes in the places where they are installed, especially because, by attracting companies, they provide job creation, industrialization and increased exports. In Brazil, they can contribute decisively to overcome major obstacles or decrease the attraction of economic agents and economic development of the country. In the case of an instrument known to be effective to achieve the goals established by the Constitution, it is duty of the Executive to push for the law that governs this customs regime is effectively applied. If the Executive doesn t fulfill this duty, incurs into unjustifiable omission, correction likely by the Judiciary, whose mission is to prevent acts or omissions contrary to constitutional order

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The present study had the objective to identify to the Social Representations of the professionals of medicine and nursing superior level of the Program Health of the Family concerning the assistance for the gestation. The research was qualitative under the optics of the Theory of the Social Representations of Serge Moscovici, of the Central Nucleus of Jean-Claude Abric and of the Analysis of Content of Laurence Bardin. We worked with the following instruments for the collection of data: Questionnaires, with social-demographic data; Free association of Words, with the inductive terms Pregnancy, Assistance for Gestation and Care; Production of mental image and half-structuralized Interview, with the following question: What does the assistance for the gestation represent for you? . We interviewed all the professionals of nursing and medicine of the Program Health of the Family in the city of Santa Cruz /RN (ten for each profession) in the period of February and March of 2007. From the analysis of the social-demographics data, we respectively identified the following percentages for nursing and medicine: the feminine sex for nursing predominated (90%); the age between 24 and 33 (70 and 60%); the religion catholic (80 and 50%) and 50% of the two groups has up to two years of formation and work in the score of the research. The analysis of the others instruments resulted in two categories: Institutionalized vision and Vision of the Common-sense. In the free association of words, the category institutionalized vision is configured as Central Nucleus and of the common sense one as nucleus Peripheral, demonstrating that the Social Representations of the assistance for the gestation attendance are in the universes consensual. In the mental images, we identified to this same construction. In the content of the interviews, the institutionalized vision is permeated by the responsibility of making and the availability of having - assistance for the gestation is recommended by the Health department and necessary genders - while the vision of the common-sense can be represented by the category sort, whose role of professionals of the assistance for the gestation is to strengthen the responsibility for the woman of a maternity socially constructed. In short, the analyzed speeches reflect that, to the knowledge acquired in the academy, are incorporated in the knowledge of the daily professional, and conducted by popular myths. Medicine and nursing recognize the importance of the attendance in such a way for the chance to educate the women for the maternity as for the possibility to prevent complications, but in its speeches they had excluded from this process the masculine figure. We conclude that the meaning of the inductive term take care, part of the common-sense and is incorporated the institutionalized speech to humanize the assistance. However, the pregnancy ceases from being seen in its natural biological direction and starts to be analyzed as a moment of fragility and predisposition the illnesses. Finally, the social nursing and the central nucleus representations for the assistance in gestation for medicine is anchored in the speeches institutionalized and of the common-sense, reflecting the concern in establishing a humanized assistance with quality

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The Family Health Strategy (ESF) is emerging as a possible restructuring of services and new practices of intervention in health care; it requires skilled professionals to work with that framework. Within this purpose, we established the Education Programme for Work and Health (PET-Saúde), in order to integrate teaching and service activities, focusing on primary care. On this basis, the aim of this work is to apprehend the social representation of nurse, doctor and dentist (Project PET-Natal Health RN preceptors) on the ESF, while practice field of them. It is a descriptive and exploratory study, with a qualitative approach, carried out in 07 Family Health Units (USF) included in the PET-Saúde Natal (RN). The population was composed of 35 professional components of the primary care team with bachelor's degree of the USF linked to this project. The sample was composed of 05 nurses, 05 physicians and 05 dentists, for a total of 15 subjects. Data were collected through three instruments: the drawing-themed story, a semi-structured individual interviews and field diary. The data relating to the identification of the subjects were entered and tabulated by the Microsoft Excel software 2007 version. The drawing analysis and interpretation is given by the significance attributed to the resource chart from title and keywords assigned by the subjects, considering the ESF as an inductive term. The stories and interviews were transcribed and typed and then subjected to read/listen the material and a lexical analysis through Alceste. After this process, the discursive material was analyzed and discussed by theoretical and methodological feature of the Social Representations theory. The majority of health professionals were female, aged between 46 and 52 years old, married, income less than six minimum wage, time since graduation ranged from 22 to 29 years and working time in the ESF range from 02 to 11 years. From the classification system ALCESTE were selected categories identified by: Category 1 - ESF: relations and territory; Category 2 - Training and bond profile; Category 3 - Working process in the ESF; Category 4 - Articulation between teaching and service; Category 5 - Health care and disease prevention. The representational field construction, while a process, followed the logic of structural cores in existing categories. In this sense, it is clear that the ESF is an environment rich in diversity, experience and relationships with potential such as the relationship "very subject-subject" and the link established between professional-community, but also has some weaknesses such as poor working conditions, lack of popular participation and management support, thus difficulties in the achievement of teamwork. Being essential to that end, the teaching-service aimed at the formation of a new health professional able to work in the ESF. In this research, the training of the representational field encountered a diversity of structural cores, or thoughts on training, about the ESF because of the greater emphasis on the here and now of the interaction between health professionals, the ESF, the community, PET Health-UFRN and students, emphasizing that such proposals are still considered as concepts in the context of recent health and that, therefore, are not fully realized in the social imaginary

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The usual programs for load flow calculation were in general developped aiming the simulation of electric energy transmission, subtransmission and distribution systems. However, the mathematical methods and algorithms used by the formulations were based, in majority, just on the characteristics of the transmittion systems, which were the main concern focus of engineers and researchers. Though, the physical characteristics of these systems are quite different from the distribution ones. In the transmission systems, the voltage levels are high and the lines are generally very long. These aspects contribute the capacitive and inductive effects that appear in the system to have a considerable influence in the values of the interest quantities, reason why they should be taken into consideration. Still in the transmission systems, the loads have a macro nature, as for example, cities, neiborhoods, or big industries. These loads are, generally, practically balanced, what reduces the necessity of utilization of three-phase methodology for the load flow calculation. Distribution systems, on the other hand, present different characteristics: the voltage levels are small in comparison to the transmission ones. This almost annul the capacitive effects of the lines. The loads are, in this case, transformers, in whose secondaries are connected small consumers, in a sort of times, mono-phase ones, so that the probability of finding an unbalanced circuit is high. This way, the utilization of three-phase methodologies assumes an important dimension. Besides, equipments like voltage regulators, that use simultaneously the concepts of phase and line voltage in their functioning, need a three-phase methodology, in order to allow the simulation of their real behavior. For the exposed reasons, initially was developped, in the scope of this work, a method for three-phase load flow calculation in order to simulate the steady-state behaviour of distribution systems. Aiming to achieve this goal, the Power Summation Algorithm was used, as a base for developing the three phase method. This algorithm was already widely tested and approved by researchers and engineers in the simulation of radial electric energy distribution systems, mainly for single-phase representation. By our formulation, lines are modeled in three-phase circuits, considering the magnetic coupling between the phases; but the earth effect is considered through the Carson reduction. It s important to point out that, in spite of the loads being normally connected to the transformer s secondaries, was considered the hypothesis of existence of star or delta loads connected to the primary circuit. To perform the simulation of voltage regulators, a new model was utilized, allowing the simulation of various types of configurations, according to their real functioning. Finally, was considered the possibility of representation of switches with current measuring in various points of the feeder. The loads are adjusted during the iteractive process, in order to match the current in each switch, converging to the measured value specified by the input data. In a second stage of the work, sensibility parameters were derived taking as base the described load flow, with the objective of suporting further optimization processes. This parameters are found by calculating of the partial derivatives of a variable in respect to another, in general, voltages, losses and reactive powers. After describing the calculation of the sensibility parameters, the Gradient Method was presented, using these parameters to optimize an objective function, that will be defined for each type of study. The first one refers to the reduction of technical losses in a medium voltage feeder, through the installation of capacitor banks; the second one refers to the problem of correction of voltage profile, through the instalation of capacitor banks or voltage regulators. In case of the losses reduction will be considered, as objective function, the sum of the losses in all the parts of the system. To the correction of the voltage profile, the objective function will be the sum of the square voltage deviations in each node, in respect to the rated voltage. In the end of the work, results of application of the described methods in some feeders are presented, aiming to give insight about their performance and acuity

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This work describes the study, the analysis, the project methodology and the constructive details of a high frequency DC/AC resonant series converter using sequential commutation techniques for the excitation of an inductive coupled thermal plasma torch. The aim of this thesis is to show the new modulation technique potentialities and to present a technological option for the high-frequency electronic power converters development. The resonant converter operates at 50 kW output power under a 400 kHz frequency and it is constituted by inverter cells using ultra-fast IGBT devices. In order to minimize the turn-off losses, the inverter cells operates in a ZVS mode referred by a modified PLL loop that maintains this condition stable, despite the load variations. The sequential pulse gating command strategy used it allows to operate the IGBT devices on its maximum power limits using the derating and destressing current scheme, as well as it propitiates a frequency multiplication of the inverters set. The output converter is connected to a series resonant circuit constituted by the applicator ICTP torch, a compensation capacitor and an impedance matching RF transformer. At the final, are presented the experimental results and the many tests achieved in laboratory as form to validate the proposed new technique

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The search for ever smaller device and without loss of performance has been increasingly investigated by researchers involving applied electromagnetics. Antennas using ceramics materials with a high dielectric constant, whether acting as a substract element of patch radiating or as the radiant element are in evidence in current research, that due to the numerous advantages offered, such as: low profile, ability to reduce the its dimensions when compared to other devices, high efficiency of ratiation, suitability the microwave range and/or millimeter wave, low temperature coefficient and low cost. The reason for this high efficiency is that the dielectric losses of ceramics are very low when compared to commercially materials sold used in printed circuit boards, such as fiberglass and phenolite. These characteristics make ceramic devices suitable for operation in the microwave band. Combining the design of patch antennas and/or dielectric resonator antenna (DRA) to certain materials and the method of synthesis of these powders in the manufacture of devices, it s possible choose a material with a dielectric constant appropriate for the design of an antenna with the desired size. The main aim of this work is the design of patch antennas and DRA antennas on synthesis of ceramic powders (synthesis by combustion and polymeric precursors - Pe- chini method) nanostructured with applications in the microwave band. The conventional method of mix oxides was also used to obtain nanometric powders for the preparation of tablets and dielectric resonators. The devices manufactured and studied on high dielectric constant materials make them good candidates to have their small size compared to other devices operating at the same frequency band. The structures analyzed are excited by three different techniques: i) microstrip line, ii) aperture coupling and iii) inductive coupling. The efficiency of these techniques have been investigated experimentally and compared with simulations by Ansoft HFSS, used in the accurate analysis of the electromagnetic behavior of antennas over the finite element method (FEM). In this thesis a literature study on the theory of microstrip antennas and DRA antenna is performed. The same study is performed about the materials and methods of synthesis of ceramic powders, which are used in the manufacture of tablets and dielectric cylinders that make up the devices investigated. The dielectric media which were used to support the analysis of the DRA and/or patch antennas are analyzed using accurate simulations using the finite difference time domain (FDTD) based on the relative electrical permittivity (er) and loss tangent of these means (tand). This work also presents a study on artificial neural networks, showing the network architecture used and their characteristics, as well as the training algorithms that were used in training and modeling some parameters associated with the devices investigated

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The usual programs for load flow calculation were in general developped aiming the simulation of electric energy transmission, subtransmission and distribution systems. However, the mathematical methods and algorithms used by the formulations were based, in majority, just on the characteristics of the transmittion systems, which were the main concern focus of engineers and researchers. Though, the physical characteristics of these systems are quite different from the distribution ones. In the transmission systems, the voltage levels are high and the lines are generally very long. These aspects contribute the capacitive and inductive effects that appear in the system to have a considerable influence in the values of the interest quantities, reason why they should be taken into consideration. Still in the transmission systems, the loads have a macro nature, as for example, cities, neiborhoods, or big industries. These loads are, generally, practically balanced, what reduces the necessity of utilization of three-phase methodology for the load flow calculation. Distribution systems, on the other hand, present different characteristics: the voltage levels are small in comparison to the transmission ones. This almost annul the capacitive effects of the lines. The loads are, in this case, transformers, in whose secondaries are connected small consumers, in a sort of times, mono-phase ones, so that the probability of finding an unbalanced circuit is high. This way, the utilization of three-phase methodologies assumes an important dimension. Besides, equipments like voltage regulators, that use simultaneously the concepts of phase and line voltage in their functioning, need a three-phase methodology, in order to allow the simulation of their real behavior. For the exposed reasons, initially was developped, in the scope of this work, a method for three-phase load flow calculation in order to simulate the steady-state behaviour of distribution systems. Aiming to achieve this goal, the Power Summation Algorithm was used, as a base for developping the three phase method. This algorithm was already widely tested and approved by researchers and engineers in the simulation of radial electric energy distribution systems, mainly for single-phase representation. By our formulation, lines are modeled in three-phase circuits, considering the magnetic coupling between the phases; but the earth effect is considered through the Carson reduction. Its important to point out that, in spite of the loads being normally connected to the transformers secondaries, was considered the hypothesis of existence of star or delta loads connected to the primary circuit. To perform the simulation of voltage regulators, a new model was utilized, allowing the simulation of various types of configurations, according to their real functioning. Finally, was considered the possibility of representation of switches with current measuring in various points of the feeder. The loads are adjusted during the iteractive process, in order to match the current in each switch, converging to the measured value specified by the input data. In a second stage of the work, sensibility parameters were derived taking as base the described load flow, with the objective of suporting further optimization processes. This parameters are found by calculating of the partial derivatives of a variable in respect to another, in general, voltages, losses and reactive powers. After describing the calculation of the sensibility parameters, the Gradient Method was presented, using these parameters to optimize an objective function, that will be defined for each type of study. The first one refers to the reduction of technical losses in a medium voltage feeder, through the installation of capacitor banks; the second one refers to the problem of correction of voltage profile, through the instalation of capacitor banks or voltage regulators. In case of the losses reduction will be considered, as objective function, the sum of the losses in all the parts of the system. To the correction of the voltage profile, the objective function will be the sum of the square voltage deviations in each node, in respect to the rated voltage. In the end of the work, results of application of the described methods in some feeders are presented, aiming to give insight about their performance and acuity

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This work discusses the design of a transformer used in a plant plasma. This plant, which is being developed in UFRN, will be used in the treatment of waste. It consists basically of a radio frequency power supply and a inductive plasma torch. The transformer operates at the nominal frequency of 400 kHz, with 50 kW, allowing the adaptation of impedance between the power supply and torch. To develop the project, a study was done on the fabrication technologies and physical effects on the frequency of operation. This was followed by the modeling of this transformer. Finally, simulations and tests were conducted to validate the design

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To enhance the maintenance practices, Oil and Gas Pipelines are inspected from the inside by automated systems called PIG (Pipeline Inspection Gauge). The inspection and mapping of defects, as dents and holes, in the internal wall of these pipelines are increasingly put into service toward an overall Structural Integrity Policy. The residual life of these structures must be determined such that minimize its probability of failure. For this reason, the investigation on the detection limits of some basic topological features constituted by peaks or valleys disposed along a smooth surface is of great value for determining the sensitivity of the measurements of defects from some combinations of circumferential, axial and radial extent. In this investigation, it was analyzed an inductive profilometric sensor to scan three races, radius r1, r2, r3, in a circular surface of low carbon steel, equipped with eight consecutive defects simulated by bulges and holes by orbit, equally spaced at p/4 rad. A test rig and a methodology for testing in laboratory were developed to evaluate the sensor response and identify their dead zones and jumps due to fluctuations as a function of topological features and scanning velocity, four speeds different. The results are presented, analyzed and suggestions are made toward a new conception of sensor topologies, more sensible to detect these type of damage morphologies

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Recent research has revealed that the majority of Biology teachers believe the practice of experimental activities as a didactical means would be the solution for the improvement of the Biology teaching-learning process. There are, however, studies which signal the lack of efficiency in such practice lessons as far as building scientific knowledge is concerned. It is also said that despite the enthusiasm on the teachers‟ part, such classes are rarely taught in high school. Several studies point pedagogical difficulties as well as nonexistence of a minimal infrastructure needed in laboratories as cause of low frequency in experimental activities. The poor teacher performance in terms of planning and development of classes; the large number of students per class; lack of financial stimulus for teachers are other reasons to be taken into account among others, in which can also be included difficulties of epistemological nature. That means an unfavorable eye of the teacher towards experimental activities. Our study aimed to clarify if such scenario is generalized in high schools throughout the state of Rio Grande do Norte Brazil. During our investigation a sample of twenty teaching institutions were used. They were divided in two groups: in the first group, five IFRN- Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Norte schools. Two of those in Natal, and the other three from the country side. The second group is represented by fifteen state schools belonging to the Natal metropolitan area. The objectives of the research were to label schools concerning laboratory facilities; to identify difficulties pointed by teachers when performing experiment classes, and to become familiar with the conceptions of the teachers in regarding biology experiment classes. To perform such task, a questionnaire was used as instrument of data collecting. It contained multiple choice, essay questions and a semi-structured interview with the assistance of a voice recorder. The data analysis and the in loco observation allowed the conclusion that the federal schools do present better facilities for the practice of experimental activities when compared to state schools. Another aspect pointed is the fact that teachers of federal schools have more time available for planning the experiments; they are also better paid and are given access a career development, which leads to better salaries. All those advantages however, do not show a significantly higher frequency regarding the development of experiments when compared to state school teachers. Both teachers of federal and state schools pointed infra-structure problems such as the availability of reactants, equipments and consumption supplies as main obstacle to the practice of experiments in biology classes. Such fact leads us to conclude that maybe there are other problems not covered by the questionnaire such as poor ability to plan and execute experimental activities. As far as conceptions about experimental activities, it was verified in the majority of the interviewees a inductive-empiric point of view of science possibly inherited during their academic formation and such point of view reflected on the way they plan and execute experiments with students