Detecção de fraudes em leitores de impressões digitais sem contato utilizando descritores de texturas e redes neurais artificiais

Monografia (graduação)—Universidade de Brasília, Instituto de Ciências Exatas, Departamento de Ciência da Computação, 2015.Com o advento dos sistemas biométricos de impressão digital, surgem também as mais diversas técnicas de ataque que visam enganar a segurança imposta. Quando um atacante investe contra um sistema, três possíveis situações merecem destaque. Em uma delas, o atacante fornece uma impressão digital falsa com o objetivo de se passar por um terceiro. Na outra, o atacante altera sua impressão digital de forma a não ser reconhecido. Ainda, há situações nas quais um usuário insere objetos no leitor, ou seja, não são apresentadas impressões digitais. Para que tais tentativas de fraude sejam combatidas, este trabalho apresenta um método capaz de classificar imagens provenientes de um leitor biométrico de impressões digitais sem contato em categorias que indicam a presença de dedos reais, dedos oclusos e objetos que não são dedos. A classificação é realizada com uma combinação de redes neurais artificiais e os descritores de textura ILBP e GLCM. _____________________________________________________________________________ ABSTRACTAlong with the advent of biometric systems, many techniques have been created in order to trick them. Many times, these techniques are performed at the sensor level and, according to the way it is done, they may be classified into 3 subcategories. Two of them are worth mentioning for the purpose of this paper. In one of them, the attacker provides a fake fingerprint to make the system believe that the attacker is a valid user. In the other, the attacker obfuscates his fingerprint so that the system will not be able to identify him. There is also the situation that a user presents an object to the sensor, in which case there is no fingerprint. This paper proposes an anti-spoofing method that classifies images acquired from a touchless fingreprint biometric sensor into three categories: real fingerprint, obfuscated fingerprint or not even a finger. The proposed method makes use of artificial neural networks and a combination of two texture descriptors: ILBP and GLCM

NDE of Metal Surface Breaking Cracks Under Adhesive Coating

Initiation and propagation of surface breaking cracks is a major factor limiting life of many engineering structures [1]. A significant effort has been expended towards developing non-destructive methods to detect and size surface breaking cracks [2]–[5]. Due to their high sensitivity ultrasonic and eddy current methods are the two most widely used in practical inspections. For example, surface acoustic wave is capable of detecting a 50¼m deep semicircular crack [4, 5]. About the same size cracks can be detected by eddy current method in a number of conducting materials

Labels for non-individuals

Quasi-set theory is a first order theory without identity, which allows us to cope with non-individuals in a sense. A weaker equivalence relation called ``indistinguishability'' is an extension of identity in the sense that if $x$ is identical to $y$ then $x$ and $y$ are indistinguishable, although the reciprocal is not always valid. The interesting point is that quasi-set theory provides us a useful mathematical background for dealing with collections of indistinguishable elementary quantum particles. In the present paper, however, we show that even in quasi-set theory it is possible to label objects that are considered as non-individuals. We intend to prove that individuality has nothing to do with any labelling process at all, as suggested by some authors. We discuss the physical interpretation of our results.Comment: 11 pages, no figure

The effect of loading direction and Sn alloying on the deformation modes of Zr: An in-situ neutron diffraction study

Deformation modes (slip and twining) in a strongly textured model hcp alloy system (Zr–Sn) have been investigated using in-situ neutron diffraction and deformation along with complementary electron microscopy. Analysis of the evolution of the intergranular strain evolutions and intensity of specific reflections from neutron diffraction show differential influence of Sn on the extent of twinning too, depending on the deformation direction. While Sn displayed very noticeable influence on twin activity when samples were compressed along a direction that predominantly activates prismatic slip, this effect was not seen when samples were compressed along other different directions. These experimental observations were successfully simulated using a CPFE (crystal plasticity finite element) model that incorporates composition sensitive CRSS (critical resolved shear stress) for slip and composition insensitive CRSS activation of twinning. The success of the CPFE model in capturing the experimental observations with respect to twin evolution suggests that the twinning in Zr is chiefly governed by the initial crystallographic texture and the associated intergranular stress state generated during plastic deformation

Brazils Highway BR-319: The road to the collapse of the Amazon and the violation of indigenous rights

One of the greatest threats to the Brazilian Amazon is the reconstruction and paving of the formerly abandoned Highway BR-319, which would link one of the most conserved blocks in the Amazon forest to the “arc of deforestation” on the southern edge of the region where most forest has already been destroyed. BR-319 and its planned side roads would allow the actors and processes from the arc of deforestation to move into vast areas of unprotected rainforest. In the specific case of this highway, a judicial decision that is not subject to further appeal established that environmental studies for the first section of the highway to be reconstructed (“Lot C”) must be carried out before paving. The federal highway department and the “Civil House” of President Bolsonaro’s presidential office ignored this decision and issued a call for bids for the construction work. Due to the current lack of governance in the BR-319 area and the history of deforestation whenever Amazonian highways are built, the decision on whether to suspend the contract for the “Lot C” is critical for the maintenance of both the ecosystem services of the Amazon forest and the way of life of indigenous and riverside people. This decision is expected to be made shortly by a single person

A meta-analytic review of stand-alone interventions to improve body image

Objective Numerous stand-alone interventions to improve body image have been developed. The present review used meta-analysis to estimate the effectiveness of such interventions, and to identify the specific change techniques that lead to improvement in body image. Methods The inclusion criteria were that (a) the intervention was stand-alone (i.e., solely focused on improving body image), (b) a control group was used, (c) participants were randomly assigned to conditions, and (d) at least one pretest and one posttest measure of body image was taken. Effect sizes were meta-analysed and moderator analyses were conducted. A taxonomy of 48 change techniques used in interventions targeted at body image was developed; all interventions were coded using this taxonomy. Results The literature search identified 62 tests of interventions (N = 3,846). Interventions produced a small-to-medium improvement in body image (d+ = 0.38), a small-to-medium reduction in beauty ideal internalisation (d+ = -0.37), and a large reduction in social comparison tendencies (d+ = -0.72). However, the effect size for body image was inflated by bias both within and across studies, and was reliable but of small magnitude once corrections for bias were applied. Effect sizes for the other outcomes were no longer reliable once corrections for bias were applied. Several features of the sample, intervention, and methodology moderated intervention effects. Twelve change techniques were associated with improvements in body image, and three techniques were contra-indicated. Conclusions The findings show that interventions engender only small improvements in body image, and underline the need for large-scale, high-quality trials in this area. The review identifies effective techniques that could be deployed in future interventions

Establishing a core outcome set for peritoneal dialysis : report of the SONG-PD (standardized outcomes in nephrology-peritoneal dialysis) consensus workshop

Outcomes reported in randomized controlled trials in peritoneal dialysis (PD) are diverse, are measured inconsistently, and may not be important to patients, families, and clinicians. The Standardized Outcomes in Nephrology-Peritoneal Dialysis (SONG-PD) initiative aims to establish a core outcome set for trials in PD based on the shared priorities of all stakeholders. We convened an international SONG-PD stakeholder consensus workshop in May 2018 in Vancouver, Canada. Nineteen patients/caregivers and 51 health professionals attended. Participants discussed core outcome domains and implementation in trials in PD. Four themes relating to the formation of core outcome domains were identified: life participation as a main goal of PD, impact of fatigue, empowerment for preparation and planning, and separation of contributing factors from core factors. Considerations for implementation were identified: standardizing patient-reported outcomes, requiring a validated and feasible measure, simplicity of binary outcomes, responsiveness to interventions, and using positive terminology. All stakeholders supported inclusion of PD-related infection, cardiovascular disease, mortality, technique survival, and life participation as the core outcome domains for PD

Premating Reproductive Barriers between Hybridising Cricket Species Differing in Their Degree of Polyandry

Understanding speciation hinges on understanding how reproductive barriers arise between incompletely isolated populations. Despite their crucial role in speciation, prezygotic barriers are relatively poorly understood and hard to predict. We use two closely related cricket species, Gryllus bimaculatus and G. campestris, to experimentally investigate premating barriers during three sequential mate choice steps. Furthermore, we experimentally show a significant difference in polyandry levels between the two species and subsequently test the hypothesis that females of the more polyandrous species, G. bimaculatus, will be less discriminating against heterospecific males and hence hybridise more readily. During close-range mating behaviour experiments, males showed relatively weak species discrimination but females discriminated very strongly. In line with our predictions, this discrimination is asymmetric, with the more polyandrous G. bimaculatus mating heterospecifically and G. campestris females never mating heterospecifically. Our study shows clear differences in the strength of reproductive isolation during the mate choice process depending on sex and species, which may have important consequences for the evolution of reproductive barriers

Elastic Wave Scattering Methods: Assessments and Suggestions

I was asked by the meeting organizers to review and assess the developments over the past ten or so years in elastic wave scattering methods and to suggest areas of future research opportunities. I will highlight the developments, focusing on what I feel were distinct steps forward in our theoretical understanding of how elastic waves interact with flaws. For references and illustrative figures, I decided to use as my principal source the proceedings of the various annual Reviews of Progress in Quantitative Nondestructive Evaluation (NDE). These meetings have been the main forum not only for presenting results of theoretical research but also for demonstrating the relevance of the theoretical research for the design and interpretation of experiment. In my opinion a quantitative NDE is possible only if this relevance exists, and my major objective is to discuss and illustrate the degree to which relevance has developed. I apologize if any one feels slighted by my not mentioning a particular work To keep the size of “review” manageable, I had to be brief and to the point

Capitalizing on opportunities provided by pasture sudden death to enhance livestock sustainable management in Brazilian Amazonia

Brazil has the largest commercial beef cattle stock on Earth, and most of the cattle produced in the country is bred and finished on pastures. The cattle ranching sector represents a significant source of the country's greenhouse gas (GHG) emissions. Agricultural intensification has been highlighted as one of the main strategies in reaching global food security and reducing deforestation. The Sudden Death Disease (SDD) of pastures, which affects the most planted cultivar of Urochloa brizantha, is degrading pastures in the Amazon, contributing to low production yields and high emission rates. This paper discusses the intensification of pasture production systems and SDD, to examine the potential for pasture renovation to address livestock productivity and GHG balance, emissions and potential sinks. Does SDD represent a blessing or a curse to climate change mitigation in the Brazilian Amazon? A collection of pasture samples were assessed to measure wet and dry weight in areas with and without SDD, which were related to remote sensing data to provide an overall estimate of the total area affected by the SDD in Alta Floresta, a municipal county of southern Brazilian Amazonia. We found that 77.1% of all pastures had been committed to the syndrome, which has forced farmers to renew their pastures. This also has great potential in increasing soil carbon stocks, effectively reducing the CO2 footprint of meat production in those areas. Therefore, we firmly believe that SDD management has provided an opportunity to rebalance the emissions/sequestration equation associated with meat production by the cattle ranching sector in this Amazonin frontier