24 resultados para "scanner" ótico e ganhos genéticos
Resumo:
Antenna arrays are able to provide high and controlled directivity, which are suitable for radiobase stations, radar systems, and point-to-point or satellite links. The optimization of an array design is usually a hard task because of the non-linear characteristic of multiobjective, requiring the application of numerical techniques, such as genetic algorithms. Therefore, in order to optimize the electronic control of the antenna array radiation pattem through genetic algorithms in real codification, it was developed a numerical tool which is able to positioning the array major lobe, reducing the side lobe levels, canceling interference signals in specific directions of arrival, and improving the antenna radiation performance. This was accomplished by using antenna theory concepts and optimization methods, mainly genetic algorithms ones, allowing to develop a numerical tool with creative genes codification and crossover rules, which is one of the most important contribution of this work. The efficiency of the developed genetic algorithm tool is tested and validated in several antenna and propagation applications. 11 was observed that the numerical results attend the specific requirements, showing the developed tool ability and capacity to handle the considered problems, as well as a great perspective for application in future works.
Resumo:
The pattern classification is one of the machine learning subareas that has the most outstanding. Among the various approaches to solve pattern classification problems, the Support Vector Machines (SVM) receive great emphasis, due to its ease of use and good generalization performance. The Least Squares formulation of SVM (LS-SVM) finds the solution by solving a set of linear equations instead of quadratic programming implemented in SVM. The LS-SVMs provide some free parameters that have to be correctly chosen to achieve satisfactory results in a given task. Despite the LS-SVMs having high performance, lots of tools have been developed to improve them, mainly the development of new classifying methods and the employment of ensembles, in other words, a combination of several classifiers. In this work, our proposal is to use an ensemble and a Genetic Algorithm (GA), search algorithm based on the evolution of species, to enhance the LSSVM classification. In the construction of this ensemble, we use a random selection of attributes of the original problem, which it splits the original problem into smaller ones where each classifier will act. So, we apply a genetic algorithm to find effective values of the LS-SVM parameters and also to find a weight vector, measuring the importance of each machine in the final classification. Finally, the final classification is obtained by a linear combination of the decision values of the LS-SVMs with the weight vector. We used several classification problems, taken as benchmarks to evaluate the performance of the algorithm and compared the results with other classifiers
Resumo:
Universidade Federal do Rio Grande do Norte
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Resumo:
The main specie of marine shrimp raised at Brazil and in the world is Litopenaeus vannamei, which had arrived in Brazil in the `80s. However, the entry of infectious myonecrosis virus (IMNV), causing the infectious myonecrosis disease in marine shrimps, brought economic losses to the national shrimp farming, with up to 70% of mortality in the shrimp production. In this way, the objective was to evaluate the survival of shrimps Litopenaeus vannamei infected with IMNV using the non parametric estimator of Kaplan-Meier and a model of frailty for grouped data. It were conducted three tests of viral challenges lasting 20 days each, at different periods of the year, keeping the parameters of pH, temperature, oxygen and ammonia monitored daily. It was evaluated 60 full-sib families of L. vannamei infected by IMNV in each viral challenge. The confirmation of the infection by IMNV was performed using the technique of PCR in real time through Sybr Green dye. Using the Kaplan-Meier estimator it was possible to detect significant differences (p <0.0001) between the survival curves of families and tanks and also in the joint analysis between viral challenges. It were estimated in each challenge, genetic parameters such as genetic value of family, it`s respective rate risk (frailty), and heritability in the logarithmic scale through the frailty model for grouped data. The heritability estimates were respectively 0.59; 0.36; and 0.59 in the viral challenges 1; 2; and 3, and it was also possible to identify families that have lower and higher rates of risk for the disease. These results can be used for selecting families more resistant to the IMNV infection and to include characteristic of disease resistance in L. vannamei into the genetic improvement programs
Resumo:
This study analysed the relationship between the production of argumentative discourses and the development and (re)signification of ethical/moral concepts, conceptions and reasoning. It focused on ethical-argumentative reasoning concerning other people and their different points of view. The specific aims of this research were: (1) to investigate the considering alternative positions on adolescents previous views on a specific topic; (2) to verify whether the ability to generate counterarguments was associated with higher levels of moral reasoning, according to Kohlberg theory, and (3) to have a better comprehension of a possible relationship between adolescents abilities to use cognitive and verbal-argumentative strategies and the (re) signification of concepts/beliefs of an ethical/moral nature, and also the solution of conflicts of the same nature. The participants in this study were seventh grade students of private and public schools. Four empirical tasks were used in order to evaluate argumentative and moral reasoning. These tasks focused on: the evaluation of moral dilemmas (DIT); the evaluation of moral dilemmas with the presentation of a written justification for subjects responses; the production of arguments and the reaction to counterarguments. There was also a group-debate situation in which both argumentation and the discussion ethical/moral issues were observed. The moral dilemmas tasks aimed to evaluate the level of moral reasoning of the participants. The argumentation tasks investigated whether the adolescents generated and justified a point of view and how they dealt with counterarguments or alternative information which could lead the participants to modify their initial positions on the topic under discussion in a monological situation as well as in a group-debate setting. The results showed that, in a monological situation, most of the adolescents produced only a partial developed argumentative discourse, whereas in a more social-verbal interaction situation their discourse appeared to be more elaborated. As a general result, it was observed that the confrontation with the other s views, or dealing with counterarguments allow the adolescents to re-evaluate and re-elaborate their own views on a debatable topic. Regarding the relationship between counterargumentation and moral reasoning, it was verified that there was a subtle tendency associating the two processes. However, other factors, such as, social, emotional and cultural aspects might also influence the development of moral reasoning
Resumo:
The dissertation proposes a discussion about the instrumentality of the Social Work, in the attempt of visualizing her, as well as the profession, in a totality perspective to the light of the rationality critical-dialetical. Understood as the capacity that the professional subjects acquire of giving answers to the demands that are placed to the profession, itself built partner-historically, in a teleologys conflicts and causalitys. So, it is proposed the discussion of the instrumentality while a group of you know specific, composed essentially by the development of three practical-formative dimensions. The theoretical-methodological refers to the capacity of apprehension of the method and of the theories and, consequently, of the relationship that does with the practice. The dimension ethical-politics concerns the development of the capacity of analyzing the society and the own profession as field of contradictory forces, being considered the character eminently political of the professional exercise, as well as the professional's conscience concerning the social direction that prints in your intervention. And the technician-operative dimension refers more strictly to the technical elements and you score for the development of the intervention. It was looked for to evidence as those dimensions they attend in the professional exercise, starting from the experience lived by the social workers of the Social Attendance Reference Centers, in Natal/RN
Resumo:
Health policies in Brazil, the decentralization of SUS management responsibilities for the three spheres of government has driven the creation and regulation of the audits of health services in the National Audit Office, this is a trend of neoliberal policies imposed by international bodies like the World Bank and IMF to peripheral countries characterized by productive restructuring and reforming the state focuses on the presence of two competing projects in the area of health: Health Sector Reform Project which is based on the democratic rule of law with the assumption of health as social right and duty of the State in defending the extension of the conquest of rights and democratization of access to health care guaranteed through the public financing strategies and the effective decentralization of decisions pervaded by social control and privatized Health Project which is based on the state minimum, with a reduction in social spending or in partnerships and privatization, stronger nonprofit sector, subject to capitalist interests, is made effective through strategies targeting health policy and refilantropização actions. In this context, the present study is an analysis on the work of social audits of public health in infants from a qualitative and quantitative approach, embodied by the critical method of dialectical Marxist social theory that enabled us to unveil the characterization, the demands, challenges and outline the profile of Social Work in teams inserted audits of SUS in RN, but also provided evidence to demonstrate the prospects and possibilities of this area of activity of social workers. It was also found that through the audit work that the state fulfill its role as bureaucratic and regulator of health services with efficiency, effectiveness and economy. Yet, paradoxically, the audits of SUS may provide a vehicle for enforcing rights and ensuring the fundamental principles contained in the project of health reform, because it can be configured in a space of political struggle as representing a new field of knowledge production that needs to be appropriate for a theoretical critic able to redirect the social interests in favor of the user. From this perspective, it is concluded that the work of social audits of public health in infants despite the social relevance that prints, as they constitute an activity study of reality and its transformation proposition requires a transformative political action guided the discussion Marxist theory holds that the ethical project professional politician of Social Work
Resumo:
Classifier ensembles are systems composed of a set of individual classifiers and a combination module, which is responsible for providing the final output of the system. In the design of these systems, diversity is considered as one of the main aspects to be taken into account since there is no gain in combining identical classification methods. The ideal situation is a set of individual classifiers with uncorrelated errors. In other words, the individual classifiers should be diverse among themselves. One way of increasing diversity is to provide different datasets (patterns and/or attributes) for the individual classifiers. The diversity is increased because the individual classifiers will perform the same task (classification of the same input patterns) but they will be built using different subsets of patterns and/or attributes. The majority of the papers using feature selection for ensembles address the homogenous structures of ensemble, i.e., ensembles composed only of the same type of classifiers. In this investigation, two approaches of genetic algorithms (single and multi-objective) will be used to guide the distribution of the features among the classifiers in the context of homogenous and heterogeneous ensembles. The experiments will be divided into two phases that use a filter approach of feature selection guided by genetic algorithm