26 resultados para traveling
em Universidade Federal do Rio Grande do Norte(UFRN)
Resumo:
LINS, Filipe C. A. et al. Modelagem dinâmica e simulação computacional de poços de petróleo verticais e direcionais com elevação por bombeio mecânico. In: CONGRESSO BRASILEIRO DE PESQUISA E DESENVOLVIMENTO EM PETRÓLEO E GÁS, 5. 2009, Fortaleza, CE. Anais... Fortaleza: CBPDPetro, 2009.
Resumo:
(The Mark and Recapture Network: a Heliconius case study). The current pace of habitat destruction, especially in tropical landscapes, has increased the need for understanding minimum patch requirements and patch distance as tools for conserving species in forest remnants. Mark recapture and tagging studies have been instrumental in providing parameters for functional models. Because of their popularity, ease of manipulation and well known biology, butterflies have become model in studies of spatial structure. Yet, most studies on butterflies movement have focused on temperate species that live in open habitats, in which forest patches are barrier to movement. This study aimed to view and review data from mark-recapture as a network in two species of butterfly (Heliconius erato and Heliconius melpomene). A work of marking and recapture of the species was carried out in an Atlantic forest reserve located about 20km from the city of Natal (RN). Mark recapture studies were conducted in 3 weekly visits during January-February and July-August in 2007 and 2008. Captures were more common in two sections of the dirt road, with minimal collection in the forest trail. The spatial spread of captures was similar in the two species. Yet, distances between recaptures seem to be greater for Heliconius erato than for Heliconius melpomene. In addition, the erato network is more disconnected, suggesting that this specie has shorter traveling patches. Moving on to the network, both species have similar number of links (N) and unweighed vertices (L). However, melpomene has a weighed network 50% more connections than erato. These network metrics suggest that erato has more compartmentalized network and restricted movement than melpomene. Thus, erato has a larger number of disconnected components, nC, in the network, and a smaller network diameter. The frequency distribution of network connectivity for both species was better explained by a Power-law than by a random, Poissom distribution, showing that the Power-law provides a better fit than the Poisson for both species. Moreover, the Powerlaw erato is much better adjusted than in melpomene, which should be linked to the small movements that erato makes in the network
Resumo:
Monoculture of mind This idea, presented by Vandana Shiva, reflects the phase that we have experienced in the world: a notion of civilization that, since many decades, characterized by a technocratic big trend, has been shown as dominant and hegemonic. Based on a thinking and acting, felling and whishing standardization, this wave ends implying in what can be called of humanity‟s crisis at civilizational process. Destruction of simpler and more harmonious lifestyles with nature, human relations increasingly distant, values embrittlement, as respect, goodness and love, are some consequences of that behavioral homogenization. In the other hand, appears an archipelago of cultural and cognitive resistance against this devastating wave. Edgar Morin and Ceiça Almeida refer to this archipelago as a South Thought , what is not just a geographic question. Report, therefore, to some places, peoples, island that keep ancient costumes and knowledge, orally transmitted, for instance, from elders to younger, or vice versa, in an almost constant flow. Particular ways of experiencing the world around themselves, the men, animals, plants, rocks, or even not alive beings, masters or enchanted, spiritual guides. Next to a logic of sensitive, as Claude Levi-Strauss proposes, this reading, which is a more attentive, observer and wiser posture of surroundings, is based on touching, smelling, eating, seeing, and, I would add, felling. In light of this, I try to expatiate about certain experiences that I had the pleasure of living in some of these islands of resistance. Talks, perceptions, observations, sensations Stories, prose, poetries, music, photos, graphics Whatever could serve to portray even a bit of the reflections and forms to understand (ourselves) and produce knowledge, such as from a formation/Education to life, was well used at this ethnographic work. Space to the subjectivity and emotions I had, have, and will have a lot Everything for the dear reader may fell traveling around the world of tradition, resistance
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Particle Swarm Optimization is a metaheuristic that arose in order to simulate the behavior of a number of birds in flight, with its random movement locally, but globally determined. This technique has been widely used to address non-liner continuous problems and yet little explored in discrete problems. This paper presents the operation of this metaheuristic, and propose strategies for implementation of optimization discret problems as form of execution parallel as sequential. The computational experiments were performed to instances of the TSP, selected in the library TSPLIB contenct to 3038 nodes, showing the improvement of performance of parallel methods for their sequential versions, in executation time and results
Resumo:
The decrease in crime is one of the core issues that cause concern in society today. This study aims to propose improvements to public safety from the choice of points to the location of police units, ie the points which support the car and the police. For this, three models were developed in order to assist decision making regarding the best placement of these bases. The Model of Police Units Routing has the intention to analyze the current configuration of a given region and develop optimal routes for round preventative. The Model of Allocation and Routing for New Police Units (MARNUP) used the model of facility location called p-median weighted and traveling salesman problem (TSP) combined aiming an ideal setting for regions that do not yet have support points or to assess how far the distribution is present in relation to that found in solution. The Model Redefinition and Routing Unit Police (MRRUP) seek to change the current positioning taking into account the budgetary constraints of the decision maker. To verify the applicability of these models we used data from 602 points to instances of police command that is responsible for the capital city of Natal. The city currently has 31 police units for 36 of these 19 districts and police have some assistance. This reality can lead to higher costs and higher response times for answering emergency calls. The results of the models showed that in an ideal situation it is possible to define a distance of 500 km/round, whereas in this 900 km are covered by approximately round. However, a change from three-point lead reduced to 700 km / round which represents a decrease of 22% in the route. This reduction should help improve response time to emergency care, improving the level of service provided by the increase of solved cases, reducing police shifts and routing preventive patrols
Resumo:
Techniques of optimization known as metaheuristics have achieved success in the resolution of many problems classified as NP-Hard. These methods use non deterministic approaches that reach very good solutions which, however, don t guarantee the determination of the global optimum. Beyond the inherent difficulties related to the complexity that characterizes the optimization problems, the metaheuristics still face the dilemma of xploration/exploitation, which consists of choosing between a greedy search and a wider exploration of the solution space. A way to guide such algorithms during the searching of better solutions is supplying them with more knowledge of the problem through the use of a intelligent agent, able to recognize promising regions and also identify when they should diversify the direction of the search. This way, this work proposes the use of Reinforcement Learning technique - Q-learning Algorithm - as exploration/exploitation strategy for the metaheuristics GRASP (Greedy Randomized Adaptive Search Procedure) and Genetic Algorithm. The GRASP metaheuristic uses Q-learning instead of the traditional greedy-random algorithm in the construction phase. This replacement has the purpose of improving the quality of the initial solutions that are used in the local search phase of the GRASP, and also provides for the metaheuristic an adaptive memory mechanism that allows the reuse of good previous decisions and also avoids the repetition of bad decisions. In the Genetic Algorithm, the Q-learning algorithm was used to generate an initial population of high fitness, and after a determined number of generations, where the rate of diversity of the population is less than a certain limit L, it also was applied to supply one of the parents to be used in the genetic crossover operator. Another significant change in the hybrid genetic algorithm is the proposal of a mutually interactive cooperation process between the genetic operators and the Q-learning algorithm. In this interactive/cooperative process, the Q-learning algorithm receives an additional update in the matrix of Q-values based on the current best solution of the Genetic Algorithm. The computational experiments presented in this thesis compares the results obtained with the implementation of traditional versions of GRASP metaheuristic and Genetic Algorithm, with those obtained using the proposed hybrid methods. Both algorithms had been applied successfully to the symmetrical Traveling Salesman Problem, which was modeled as a Markov decision process
Resumo:
The problems of combinatory optimization have involved a large number of researchers in search of approximative solutions for them, since it is generally accepted that they are unsolvable in polynomial time. Initially, these solutions were focused on heuristics. Currently, metaheuristics are used more for this task, especially those based on evolutionary algorithms. The two main contributions of this work are: the creation of what is called an -Operon- heuristic, for the construction of the information chains necessary for the implementation of transgenetic (evolutionary) algorithms, mainly using statistical methodology - the Cluster Analysis and the Principal Component Analysis; and the utilization of statistical analyses that are adequate for the evaluation of the performance of the algorithms that are developed to solve these problems. The aim of the Operon is to construct good quality dynamic information chains to promote an -intelligent- search in the space of solutions. The Traveling Salesman Problem (TSP) is intended for applications based on a transgenetic algorithmic known as ProtoG. A strategy is also proposed for the renovation of part of the chromosome population indicated by adopting a minimum limit in the coefficient of variation of the adequation function of the individuals, with calculations based on the population. Statistical methodology is used for the evaluation of the performance of four algorithms, as follows: the proposed ProtoG, two memetic algorithms and a Simulated Annealing algorithm. Three performance analyses of these algorithms are proposed. The first is accomplished through the Logistic Regression, based on the probability of finding an optimal solution for a TSP instance by the algorithm being tested. The second is accomplished through Survival Analysis, based on a probability of the time observed for its execution until an optimal solution is achieved. The third is accomplished by means of a non-parametric Analysis of Variance, considering the Percent Error of the Solution (PES) obtained by the percentage in which the solution found exceeds the best solution available in the literature. Six experiments have been conducted applied to sixty-one instances of Euclidean TSP with sizes of up to 1,655 cities. The first two experiments deal with the adjustments of four parameters used in the ProtoG algorithm in an attempt to improve its performance. The last four have been undertaken to evaluate the performance of the ProtoG in comparison to the three algorithms adopted. For these sixty-one instances, it has been concluded on the grounds of statistical tests that there is evidence that the ProtoG performs better than these three algorithms in fifty instances. In addition, for the thirty-six instances considered in the last three trials in which the performance of the algorithms was evaluated through PES, it was observed that the PES average obtained with the ProtoG was less than 1% in almost half of these instances, having reached the greatest average for one instance of 1,173 cities, with an PES average equal to 3.52%. Therefore, the ProtoG can be considered a competitive algorithm for solving the TSP, since it is not rare in the literature find PESs averages greater than 10% to be reported for instances of this size.
Resumo:
The aim of this research is, starting from a Baroque reading, unfold the understanding of the poems by João Cabral de Melo Neto in the axis Pernambuco-Spain. From this perspective, the reading of poet s Obra Completa allows the appearance of two persons, one from Seville and other from the Brazilian countryside, whom curiously pulsate and reveal themselves from their homelands, Brazilian northeastern dry lands and Seville, to a labyrinthy meeting establishing a close and exciting relationship of cities apart but which mark a contiguous dialogue between both cultures. The theorical effort of this investigation permeates, approaches and contrasts the directions of, among others, Severo Sarduy (1999), Gilles Deleuze (2012) and Eugenio D Ors (unknown). Not traveling an anthropological bias, this study observes the Spanish space and the Brazilian northeastern dry lands space, joining the regional to the universal and analyzes the baroque game in the (re) construction of the both men s cultures. These elements fuse, approach and move away, causing a game of allusions to Pernambuco and Spain that show itself through a similar cultural bias and different at the same time. From this apprehension it is possible to understand the synthesis of the Brazilian arid northeast-Seville men as a update of seventeenth century Baroque coming from indexes that are shown over the particular written by João Cabral de Melo Neto, in the Iberian Baroque scenario and in the American one s
Resumo:
The leitmotif of this dissertation research is on the relationship between two fields of questioning in the Foucauldian works that may be considered, at a first glance, irreconcilable: the understanding of subject as the result of determinations, on the one hand, and its ethical stance of seeking the creation of liberty, on the other. Since, despite this apparent inconsistency, both ideas are present with much emphasis on the work of the French thinker, to understand the way Foucault articulated these two ideas was necessary to elucidate and interrelate the way in which he thought about the concepts of subject, power and liberty. Traveling with the author his intellectual itinerary, it was revealed that his conception of subject and liberty can be reconciled (although maintaining its problematic nature) and, also, both are inextricably linked each one as a result of the other. Tracing, with the author, his intellectual itinerary, it was also possible to identify and describe the fruitful conceptual tools for thinking about our own determinations and about the possibilities we have of creating new subjectivities and liberating experiences
Resumo:
The present essay shows strategies of improvement in a well succeded evolutionary metaheuristic to solve the Asymmetric Traveling Salesman Problem. Such steps consist in a Memetic Algorithm projected mainly to this problem. Basically this improvement applied optimizing techniques known as Path-Relinking and Vocabulary Building. Furthermore, this last one has being used in two different ways, in order to evaluate the effects of the improvement on the evolutionary metaheuristic. These methods were implemented in C++ code and the experiments were done under instances at TSPLIB library, being possible to observe that the procedures purposed reached success on the tests done
Resumo:
Callithrix jacchus are small primates that live in cooperative reproductive family groups. They explore their home range in search of fruits, exudates and animal prey. In this study we investigate the existence of traveling routes and its relation with the feeding habits in a group of Callithrix jacchus. The group was followed for 6 months in an area of Atlantic secondary Forest at the FLONA-ICMBio of Nísia Floresta, Rio Grande do Norte. Two observers in alternated days collected data referring to the group s location using a GPS navigation device, plotting data in 5 minute intervals, and with a position accuracy under 9 meters. All behavioral recordings were done through focal time samplings. The recording windows were 15 minutes with 1 minute intervals. The main activity was foraging, which propelled the animals to explore the environment with inconsistent intensity through the months, and correlated with the location of fruits, exudates and sleeping sites. From another standpoint, most activities were focused in the core areas that featured most sleeping sites, exudates trees and fruit trees. Insects, mostly Orthopterans, were hunted in all areas. The greater ratio of movement was registered during the last hours of sunlight, when animals returned to the sleeping sites and ate a greater number of fruits. The spatial and seasonal distribution of fruits forced the animals to travel long routes. The capacity to remember the location and navigate efficiently through feeding sources is important to save energy and time costs. Learning and familiarizing with the environment through the use of landmarks and acquisition of new information is extremely important to increase the chances of survival in a constantly changing environment
Resumo:
Social behavior of Guiana dolphins, Sotalia guianensis, at Pipa Beach, RN, Brazil: dynamics, sequence, breathing synchrony, and responses to dolphin watching. Social animals form groups that can range from temporary to permanent. Depending on the nature of the social relationships developed between individuals, groups present a particular social organization and the effect of these interactions shapes the activity patterns of these animals. This study investigates: (i) fission-fusion dynamics of Guiana dolphins, through the analysis of three dimensions of the social system (variation in spatial cohesion, variation in size and composition of groups), (ii) sequence, routine and behavioral stability, (iii) breathing intervals in synchronized groups and (iv) behavioral responses of the animals to dolphin watching. Systematic observations of Guiana dolphins were made from a platform located in cliffs about 25 m above sea level that surround Madeiro Bay, Pipa Beach. Sampling occurred from December 2007 to February 2009 between 0600 h and 1600 h, and the groups of Guiana dolphins were investigated according to their size (alone and group) and composition (adults, adults and juveniles, and adults and calves). According to the analysis of fission-fusion dynamics, Guiana dolphin groups frequently changed their composition, modifying their patterns of spatial grouping and cohesion every 20 minutes on average. More than 50% of the individuals maintained a distance of up to 2 m from other group members and new individuals were attracted to the group, especially during feeding, leaving it for foraging. Large groups were more unstable than small, while groups containing only adults were more stable than groups of adults and juveniles. According to the Z-score analysis to investigate the sequence and behavioral routine, lone individuals were more ! .7! ! involved in foraging and feeding, while resting was more common in groups. Foraging and feeding were more common in homogeneous groups (individuals of the same age class), while heterogeneous groups (different age classes) were often involved in socialization, displaying a broader behavioral repertoire. Foraging and resting behavior presented higher stability (continuous duration in minutes) than the other behaviors. The analysis of breathing intervals in synchronized groups showed significant differences depending on type of behavior, composition and area preference. During resting, breathing intervals were of longer duration, and groups with calves showed shorter breathing intervals than groups without calves. Lone individuals also preferred areas called corral , often used for the entrapment of fishes. The Markov chain analysis revealed behavioral changes in the presence of boats, according to the type of group composition. Groups composed of adults presented decreased resting and increased in traveling during the presence of boats. Groups of adults and juveniles showed a massive reduction of socialization, while the behavior transition probability traveling-traveling was higher in groups of adults and calves. In the presence of the boats, stability of resting was reduced by one third of its original duration and traveling more than doubled. The behavioral patterns analyzed are discussed in light of socio-ecological models concerning costs and benefits of proximity between individuals and behavioral optimization. Furthermore, significant changes in behavioral patterns indicate that Guiana dolphins, at Pipa Beach, have suffered the effects of tourism as a result of violation of rules of conduct established for the study area
Resumo:
The marine tucuxi, Sotalia guianensis, is one of the smallest known cetaceans, has coastal habits, and occurs from Hondures to Santa Catarina, in southern Brazil. The objective of this dissertation was to describe diving behavior of the marine tucuxi in three age classes and to analyze the cardiac capacity to dive through the examination of hearts of stranded specimens. Observations were made from October 2004 to November 2005 from a vantage point, in Curral Bay at Pipa beach-RN. We used Ad Libitum sampling and All occurrences to record the behaviors. The diving was characterized by the total exposition of the tail fluke for a few seconds, in 90° or 45° angles. Were recorded 131 dives in three behavioral contexts: foraging, traveling and socialization. The difference between juveniles and adults in dive time and fluke out at 45° or 90° to search and/or capture prey is probably influenced by the strategy used and ability to capture the prey. The frequency of fluke out at 90° for foraging in adults may be related to increased physiological efficiency of adults in comparison to juveniles. However, in the context of travel and socialization the dive time and fluke out were independent between the age classes. Dive in calves were frequent during socialization (play behavior) and traveling. This, associated with synchronic calve-adult diving suggests that a relationship of these behaviors and the acquisition of experience and foraging skills. As observed in other cetaceans, the heart (n=12) of the estuarine dolphin is broad and presents long ventricles which form a round apex. The right ventricle is long and narrow. The degree of dilatation of the aortic bulb may support the heart during diastole. The characteristic morphology of the heart and short dive duration < 2 min and depth ranged from 10m in the estuarine dolphin, can be likely at physiological adaptation for diving, typical de dolphins with coastal habits. The limitation of diving time in this specie may be influenced by anatomical and physiological restrictions
Resumo:
Synchronism is the efetivation of the same behavior at the same time by two or more individuals. In cetology only from 2000 we verify an increasing of efforts for studies of synchronic behaviors. The synchronism in cetaceans was reported for a variety of contexts, including feeding, socializing, parental care, while resting, traveling and play, during afilliation, in sexual behaviour and possible while teaching. The synchronism in behavior is influenced by environmental factors and can be modified during stress situations such as the presence of boats. The aim of this study is to explore behavior synchronism presented by the estuarine dolphin (Sotalia guianensis) in Pipa, Rio Grande do Norte state, Northeastern Brazil. A total of 414 hours of observation during the year 2006, using scan sampling method, from a land based sighting was conducted. Analyses were conducted in four steps. Firstly, we determined the pattern of activity of the groups within the bay, testing for the influence of bay configuration before and after rains periods on the activity of animals. Analyses show that forage occurs more frequently after the rainy period, but there was no change in the number of individuals or spatial cohesions between them. Secondly, we analysed the influence of turism boat traffic on the behavior of animals. We verified no changes on the bahavior of animals during the presence of boats. Finally, we tested seven hypotheses regarding the ecological and social dynamics of synchronic behavior. Environmental aspects were considered the main influence for the synchronism, no influences of age, and more selective exihibition of synchronic breathing in feeding and social displays were observed during the study period
Resumo:
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