4 resultados para return paths

em Universidade Federal do Rio Grande do Norte(UFRN)


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The Car Rental Salesman Problem (CaRS) is a variant of the classical Traveling Salesman Problem which was not described in the literature where a tour of visits can be decomposed into contiguous paths that may be performed in different rental cars. The aim is to determine the Hamiltonian cycle that results in a final minimum cost, considering the cost of the route added to the cost of an expected penalty paid for each exchange of vehicles on the route. This penalty is due to the return of the car dropped to the base. This paper introduces the general problem and illustrates some examples, also featuring some of its associated variants. An overview of the complexity of this combinatorial problem is also outlined, to justify their classification in the NPhard class. A database of instances for the problem is presented, describing the methodology of its constitution. The presented problem is also the subject of a study based on experimental algorithmic implementation of six metaheuristic solutions, representing adaptations of the best of state-of-the-art heuristic programming. New neighborhoods, construction procedures, search operators, evolutionary agents, cooperation by multi-pheromone are created for this problem. Furtermore, computational experiments and comparative performance tests are conducted on a sample of 60 instances of the created database, aiming to offer a algorithm with an efficient solution for this problem. These results will illustrate the best performance reached by the transgenetic algorithm in all instances of the dataset

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When searching for food, animals often make decisions of where to go, how long to stay in a foraging area and whether or not to return to the last visited spot. These decisions can be enhanced by cognitive traits and adjusted based on previous experience. In social insects such as ants, foraging efficiency have an impact on both individual and colony level. The present study investigated, in the laboratory, the effect of distance from food, capture success and food size, and reward rate on decisions of where to forage in Dinoponera quadriceps, a ponerine ant that forage solitarily and individually make their foraging decisions. We also investigated the influence of learning on the performance of workers over successive trips searching for food by measuring the patch residence time in each foraging trip. Four scenarios were created differing in food reward rates, food size offered and distances colony-food site. Our work has shown that as a rule-of-thumb, workers of D. quadriceps return to the place where a prey item was found on the previous trip, regardless of distance, food size and reward rate. When ants did not capture preys, they were more likely to change path to search for food. However, in one of the scenarios, this decision to switch paths when unsuccessful was less evident, possibly due to the greater variation of possible outcomes ants could experience in this scenario and cognitive constraints of D. quadriceps to predict variations of food distribution. Our results also indicated a learning process of routes of exploration as well as the food site conditions for exploration. After repeated trips, foragers reduced the patch residence time in areas that they did not capture food and quickly changed of foraging area, increasing their foraging efficiency.

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The public health is a project that struggles for a fair, resolutive and democratic health and that aims to help the collective and social bodies starting from their real needs, being totally involved with inequality and social determination issues. Thus, it is of fundamental importance to form a professional commited to this project. This current study aims to understand the perception of teachers/militants of Public Health about the graduation of Healthcare professionals. Therefore, we look forward answering the following question: Which elements are relevant to the formation of the sanitarian professional? This is a field research, descriptive and exploratory, with a qualitative approach. For data collection, we used a semi-structured interview technique with veteran professionals as sanitarians and teachers of Public Health area. The data were analyzed based on the technique of thematic analysis of subject. This technique consists in structuring the text in units, in categories according analogic reunification. In this sense, were organized three analysis categories, whose titles were guided according to the study objectives, namely: "The Institutional Formation of Sanitarians"; "Elements that contribute to the Sanitarian formation " and "Possible Paths in Sanitarian Formation". Four main elements of sanitarian formation were emphasized: technical capacity to develop a sanitation work, based on three conceptual pillars of Public Health; Framework, foundation and support on Social Sciences, in the social concepts of health; Life history of the student, implication of this with the Public Health object; Field operation, in the territory, directly integrated to the service and the health system. The intervieweds imagine a path to the sanitarian formation: the Public Health should be well explored in its theory and practice in graduation, in any health area and obviously in the graduation of Public Health; the Lato Sensu courses, especially residency, would need a theoretical upgrading, given the creation of undergraduate courses on the area; the Stricto Sensu courses, while forming researchers and teachers in the area, should develop productions involved with the health system and the object of Public Health, in order to bring an effective return, in terms of applicability, in the health system. It is suggested that such a path should be complementary, in a sense of adding knowledge as it travels through graduation, postgraduation Lato Sensu and post-graduation Stricto Sensu. The idea, in general, is that the graduate-residence set / specialization-mastering / PhD compose a linear formation, ascending and complementary. To follow all this process effectively, it is necessary, and urgent, to think of regulation strategies of the formating procedures. It is also recommended that more studies are conducted in this area, specially a more careful evaluation of the undergraduate courses in Public Health, which is a current and relatively new issue on formation in the area.

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From the context of the degree‘s creation of Spanish literature and language‘s course, at UFRN, came the motivation to make this research, that presents a literary study of a poet‘s group known as Generación del 27, that came in to light at Spain, on 1920. A lot of aspects of this study are themes of many others disciplines, of this degree (Spanish Literature II, IberianAmerican Literature, Spanish Culture, Translation in Spanish Language). This work will also serve as inspiration to new reflections and proposes of translations, as bridges between the language that goes and the other that comes. It is the Translation as comprehension‘s negotiation between languages, it is the decir casi lo mismo, here in poem‘s form (ECO, 2007), in the attempt to conclude new learning, that will be shared with undergraduate and graduate students, being at teaching area, extension or new researches. To contextualize this generation‘s studies, were elected the anthologies organized by Gerardo Diego, called Poesía Española (Antologías), published on 2007, by Ediciones Cátedras, and the Antología Comentada de La Generación del 27, wrote by Víctor García de La Concha, published on 2006, by Editorial Espasa Calpe. The research took Generacion Del 27 as their object of research and - from many others critical reading about the poetry made by those young poets, their creative vocation of aesthetics and vanguard – wanted to understand the context of literary‘s creation of those poets del 27. We form our foundation with contributions by Antonio Maravall (2009), Eugenio D‘ors (s.d) Severo Sarduy (1999), Lezama Lima (2011), Alfonso Reyes (1958) e Deleuze (2005) among others that brought the comprehension of the baroque‘s language, giving emphasis to pluridirectional movement, deconstructing it‘s linearity, creating others new forms, as returns, circles, spirals favoring encounters, detachment or equal points of departure and arrivals. In this way, the poets del 27 approached the baroque of six hundred on a re-reading, and made of the third centenary‘s celebration of the Góngora‘s a Mirada exuberante death, to the return of baroque‘s spirit. Alfonso Reyes e Rubén Darío said that real lights highlighted the paths of this poets generation: The light that desdobra scintillates on García Lorca, Jorge Gullén, Dámaso Alonso, Gerardo Diego and the bullfighter Ignacio Sánchez Mejías, poets that expressed tributes in big style to Soledades author, at Madrid‘s Caffe and all Spain.