902 resultados para Abandonment of automobiles.


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Orbiculariae consists of two major clades: the cribellate Deinopidea and the much more diverse ecribellate Araneoidea. It has been hypothesized that the higher diversity of Araneoidea is a consequence of the superiority of the viscid orb web. However, this explanation seems incomplete: for example, cribellate silk may perform better than viscid silk in some contexts. Here, we consider the hypothesis that the diversification of Araneoidea was facilitated by changes in microhabitat occupation behavior due to the cheaper viscid orb web. In the present work we investigate the idea that the reduction in site tenacity caused by the emergence of the viscid orb web has led to an increase in the exploration of different resources and to a greater diversification of the Arancoidea through the evolutionary time. To test this idea, we evaluated the response of one cribellate orb web spider (Zosis geniculata Olivier 1789, Uloboridae) and one ecribellate orb web spider (Metazygia rogenhoferi Keyserling 1878, Arancidae) to abrupt prey absence. The changes in site tenacity and the day-to-day investment in web silk were evaluated. Spiders with three-dimensional webs tend to exhibit greater site tenacity than spiders making orb webs. Zosis geniculata and M. rogenhoferi show similar site tenacity when prey is ample. When prey is unavailable, the tenacity of the cribellate species increases while the tenacity of the ecribellate remains unchanged, and the silk investment of both species decreases. However, this decrease in silk investment is more extensive in Z. geniculata. These results coincide with the idea that a less costly ecribellate orb web leads to a lower tenacity and suggest that more frequent microhabitat abandonment in a context of insect radiation (Neiptera) leads to more diverse and opportunistic exploration of microhabitats that, in the long term, may be one explanation for the greater Araneoidea diversification.

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Aeschylus and Euripides used tragic female characters to help fulfill the purpose of religious celebration and to achieve the motivation of public reaction. The playwrights, revising myths about tragic woman and redefining the Greek definition of appropriate femininity, supported or questioned the very customs which they changed. Originally composed as part of a religious festival for Dionysus, the god of wine, revelry and fertility, the tragedies of Aeschylus and Euripides were evaluated by Aristotle. He favored Aeschylus over Euripides, but it appears as if his stipulations for tragic characterization do not apply to Aeschylean and Euripidean women. Modem critics question both Aristotle's analysis in the Poetics as well as the tragedies which he evaluated. As part of the assessment of Aeschylus, the character of the Persian Queen, Atossa, appears as a conradiction the images that Greeks maintain of non-Greeks. The Persians is discussed in relation to modem criticisms and as on its function as a warning against radical changes in Athenian domestic life. The Oresteia, a trilogy, also charts the importance of an atypical woman in Aeschylean tragedy, and how this role, Clytaemnestra, represents an extreme example of the natural and necessary evolution of families, households and kingdoms. In contrast to Aeschylus' plea to retain nomoi (traditional custom and law), EUripides' tragedy, the Medea, demonstrates the importance of a family and a country to provide security, especially for women. Medea's abandonment by Jason and subsequent desperation drives her to commit murder in the hope of revenge. Ultimately, Euripides advocates changes in social convention away from the alienation of non-Greek, non-citizens, and females. Euripides is, unfortunately, tagged a misogynist by some in this tragedy and another example-the Hippolytus. Euripides' Phaedra becomes entangled in a scheme of divine vengeance and ultimately commits suicide in an attempt to avoid societal shame. Far from treatises of hate, Euripidean women take advantage of the little power they possess within a constrictive social system. While both Aeschylus and Euripides revise customary images and expectations of women in the context of religiously-motivated drama, one playwright intends to maintain civic order and the other intends to challenge the secular norm.

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In this paper I investigate the quality evolution ofBrazilian autos. To measure the quality evolution of Brazilian autos, I have assembled a data set for Brazilian passenger cars for the period 1960-1994, to which I have applied the hedonic pricing methodology. To the best of my k:nowledge, this is the first time an index of quality change has been constructed for the Brazilian automobile industry. The results presented here have two major implications. They allow a better -- ......... understanding of product innovation in Brazil's auto industry, and they provide a clearer explanation of the behavior of auto prices.

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The aim of this thesis was to evaluate historical change of the landscape of Madeira Island and to assess spatial and temporal vegetation dynamics. In current research diverse “retrospective techniques”, such as landscape repeat photography, dendrochronology, and research of historical records were used. These, combined with vegetation relevés, aimed to gather information about landscape change, disturbance history, and vegetation successional patterns. It was found that landscape change, throughout 125 years, was higher in the last five decades manly driven by farming abandonment, building growth and exotic vegetation coverage increase. Pristine vegetation was greatly destroyed since early settlement and by the end of the nineteenth century native vegetation was highly devastated due to recurrent antropogenic disturbances. These actions also helped to block plant succession and to modify floristical assemblages, affecting as well as species richness. In places with less hemeroby, although significant growth of vegetation of lower seral stages was detected, the vegetation of most mature stages headed towards unbalance between recovery and loss, being also very vulnerable to exotic species encroachment. Recovery by native vegetation also occurred in areas formerly occupied by exotic plants and agriculture but it was almost negligible. Vegetation recovery followed the successional model currently proposed, attesting the model itself. Yet, succession was slower than espected, due to lack of favourable conditions and to recurrent disturbances. Probable tempus of each seral stage was obtained by growth rates of woody taxa estimated through dendrochronology. The exotic trees which were the dominant trees in the past (Castanea sativa and Pinus pinaster) almost vanished. Eucalyptus globulus, the current main tree of the exotic forest is being replaced by other cover types as Acacia mearnsii. The latter, along with Arundo donax, Cytisus scoparius and Pittosporum undulatum are currently the exotic species with higher invasive behaviour. However, many other exotic species have also proved to be highly pervasive and came together with the ones referred above to prevent native vegetation regeneration, to diminish biological diversity, and to block early successional phases delaying native forest recovery.

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A direct version of the boundary element method (BEM) is developed to model the stationary dynamic response of reinforced plate structures, such as reinforced panels in buildings, automobiles, and airplanes. The dynamic stationary fundamental solutions of thin plates and plane stress state are used to transform the governing partial differential equations into boundary integral equations (BIEs). Two sets of uncoupled BIEs are formulated, respectively, for the in-plane state ( membrane) and for the out-of-plane state ( bending). These uncoupled systems are joined to formamacro-element, in which membrane and bending effects are present. The association of these macro-elements is able to simulate thin-walled structures, including reinforced plate structures. In the present formulation, the BIE is discretized by continuous and/or discontinuous linear elements. Four displacement integral equations are written for every boundary node. Modal data, that is, natural frequencies and the corresponding mode shapes of reinforced plates, are obtained from information contained in the frequency response functions (FRFs). A specific example is presented to illustrate the versatility of the proposed methodology. Different configurations of the reinforcements are used to simulate simply supported and clamped boundary conditions for the plate structures. The procedure is validated by comparison with results determined by the finite element method (FEM).

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The main concern of activities developed in oil and gas well construction is safety. But safety during the well construction process is not a trivial subject. Today risk evaluation approaches are based in static analyses of existent systems. In other words, those approaches do not allow a dynamic analysis that evaluates the risk for each alteration of the context. This paper proposes the use of Quantitative and Dynamic Risk Assessment (QDRA) to assess the degree of safety of each planned job. The QDRA can be understood as a safe job analysis approach, developed with the purpose of quantifying the safety degree in entire well construction and maintenance activities. The QDRA is intended to be used in the planning stages of well construction and maintenance, where the effects of hazard on job sequence are important unknowns. This paper also presents definitions of barrier, and barriers integrated set (BIS), and a modeling technique showing their relationships. (c) 2006 Elsevier B.V. All rights reserved.

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The time and the distance traveled during the acceleration and the velocity retaking are parameters used for the comparison and the project of vehicles. In this paper equations for the calculation of those parameters are presented. Several criteria are presented for the shift gears. It is also verified the occurrence or not of total slip during the acceleration of the vehicle. The theoretical models were implemented in a developed computational system. Such system was applied in a Mercedes-Benz do Brazil sample vehicle, in order to facilitate comparisons between the simulate values and the experimental road tests. Copyright © 1997 Society of Automotive Engineers, Inc.

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The fuel consumption is an important factor in the vehicle development due the fact that it has a direct effect on its trade aims. Besides that, it is known that the petrol is a scarce fuel. In this paper it is presented a procedure of fuel consumption calculation for a vehicle traveling in driving schedule. In such calculation it has been taken into account the operational conditions (load, pavement, climbing road, among others) and the building characteristics (map engine, transmission, frontal area, tire, among others) of road vehicles. There has also been an application of the theoretical model developed in a sample Mercedes-Benz do Brasil vehicle which has been compared with the values of experimental tests. Copyright © 1997 Society of Automotive Engineers, Inc.

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This paper seeks to apply a routine for highways detection through the mathematical morphology tools in high resolution image. The Mathematical Morphology theory consists of describing structures geometric presents quantitatively in the image (targets or features). This explains the use of the Mathematical Morphology in this work. As high resolution images will be used, the largest difficulty in the highways detection process is the presence of trees and automobiles in the borders tracks. Like this, for the obtaining of good results through the use of morphologic tools was necessary to choose the structuring element appropriately to be used in the functions. Through the appropriate choice of the morphologic operators and structuring elements it was possible to detect the highways tracks. The linear feature detection using mathematical morphology techniques, can contribute in cartographic applications, as cartographic products updating.

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The main objective of this paper is to make a prospective analysis about the tendencies of the world wide strategies of commercial vehicles development, in relation of the current local and international scenery. It has been done a research by using the Delphi method, which consists into regulate, systematically, the presentation of questions about a specified problem to a group of specialists. In order to guarantee more representative data, it has been adopted three distinct groups: academics, OEMs managers and Tier 1 suppliers managers. The results showed that the three mentioned groups have similar opinion about the necessity of having a product development in the subsidiaries companies; also it has been pointed the necessity of having more taylor made vehicles, due to the intrinsic characteristics of this industry segment. Copyright © 2008 SAE International.

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After nearly 80 years since the construction of its core, represented today by the city's central area, Londrina, located in the state of Parana, has the appearance of a new city but its features and trends of planning policies depict the bad examples of Brazilian cities. With a booming urban growth, from north to south of the county, the urban interstices represented by big voids in the middle of the city created speculation and the concept of an ideal city slowly disappeared. With a metropolitan appearance and, at the same time, with small town aspects, Londrina stands out as an automobile-oriented city, a fact that has impacted the livelihood of the population, generating environmental impacts for all social classes. This paper discusses how the form of occupation in Londrina, characterized by the sprawl phenomenon and its relation to car preference as a mode of transportation has generated urban environmental impacts. It was concluded that the choice of using cars in Londrina, as well in other medium-sized Brazilian cities studied by the comparative method, has increased and has generated bottlenecks in traffic. As a consequence, there is a constant expropriation of properties for widening roads and at the same time, the presence of various densities and urban voids that form an uneven urban space and an obstacle to efficient urban planning. © 2012 WIT Press.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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The expansion of the cellulosic biofuels industry throughout the United States has broad-scale implications for wildlife management on public and private lands. Knowledge is limited on the effects of reverting agriculture to native grass, and vice versa, on size of home range and habitat use of white-tailed deer (Odocoileus virginianus). We followed 68 radio-collared female deer from 1991 through 2004 that were residents of DeSoto National Wildlife Refuge (DNWR) in eastern Nebraska, USA. The refuge was undergoing conversion of vegetation out of row-crop agriculture and into native grass, forest, and emergent aquatic vegetation. Habitat in DNWR consisted of 30% crop in 1991 but removing crops to establish native grass and wetland habitat at DNWR resulted in a 44% reduction in crops by 2004. A decrease in the amount of crops on DNWR contributed to a decline in mean size of annual home range from 400 ha in 1991 to 200 ha in 2005 but percentage of crops in home ranges increased from 21% to 29%. Mean overlap for individuals was 77% between consecutive annual home ranges across 8 years, regardless of crop availability. Conversion of crop to native habitat will not likely result in home range abandonment but may impact disease transmission by increasing rates of contact between deer social groups that occupy adjacent areas. Future research on condition indices or changes in population parameters (e.g., recruitment) could be incorporated into the study design to assess impacts of habitat conversion for biofuel production.

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Purpose: Understand the difficulties and experienced of individuals suffering from postpartum depression, related to mood disturbances, the mother-child bond and its repercussions in the meanings established for the experience of being a mother. Methods: Forty-one patients were interviewed, with ages ranging from 20 to 49 years, from a total of 106 attended at the Primary Care Unit, in the interior of the state of Parahiba, Brazil. A sample of 21 women was selected, presenting an inclusion profile, propitious to mapping postpartum depression. The eligible patients were referred by two PSF (Health Family) teams (one each from the urban and rural zones), aimed at diagnosing the psychic disturbance of the perperium. They were accompanied by a psychologist and all signed an informed consent form. A field diary supported the information recorded. Beck's Depression Inventory complemented the inclusion and follow-up of the patients. The data were analyzed statistically. Results: We confirmed the findings of the most recent studies that infant abandonment in the postpartum period occurs in situations where multiple and serious factors add up, such as misery (86.7%), little schooling (67%), lack of a support network (36.5%), estrangement of the mother's family relations (12%) and lack of paternal involvement (91.5%). Conclusion: The feeling of psyching pain and suffering, resulting from postpartum depression, is the most emphasized by women (87%) because it triggers the greatest discomfort, due to the difficulty in overcoming it.

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In the last few years, the European Union (EU) has become greatly concerned about the environmental costs of road transport in Europe as a result of the constant growth in the market share of trucks and the steady decline in the market share of railroads. In order to reverse this trend, the EU is promoting the implementation of additional charges for heavy goods vehicles (HGV) on the trunk roads of the EU countries. However, the EU policy is being criticised because it does not address the implementation of charges to internalise the external costs produced by automobiles and other transport modes such as railroad. In this paper, we first describe the evolution of the HGV charging policy in the EU, and then assess its practical implementation across different European countries. Second, and of greater significance, by using the case study of Spain, we evaluate to what extent the current fees on trucks and trains reflect their social marginal costs, and consequently lead to an allocative-efficient outcome. We found that for the average case in Spain the truck industry meets more of the marginal social cost produced by it than does the freight railroad industry. The reason for this lies in the large sums of money paid by truck companies in fuel taxes, and the subsidies that continue to be granted by the government to the railroads.