902 resultados para fuzzy vault, multiple biometrics, biometric cryptosystem, biometrics and cryptography


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The unprecedented and relentless growth in the electronics industry is feeding the demand for integrated circuits (ICs) with increasing functionality and performance at minimum cost and power consumption. As predicted by Moore's law, ICs are being aggressively scaled to meet this demand. While the continuous scaling of process technology is reducing gate delays, the performance of ICs is being increasingly dominated by interconnect delays. In an effort to improve submicrometer interconnect performance, to increase packing density, and to reduce chip area and power consumption, the semiconductor industry is focusing on three-dimensional (3D) integration. However, volume production and commercial exploitation of 3D integration are not feasible yet due to significant technical hurdles.

At the present time, interposer-based 2.5D integration is emerging as a precursor to stacked 3D integration. All the dies and the interposer in a 2.5D IC must be adequately tested for product qualification. However, since the structure of 2.5D ICs is different from the traditional 2D ICs, new challenges have emerged: (1) pre-bond interposer testing, (2) lack of test access, (3) limited ability for at-speed testing, (4) high density I/O ports and interconnects, (5) reduced number of test pins, and (6) high power consumption. This research targets the above challenges and effective solutions have been developed to test both dies and the interposer.

The dissertation first introduces the basic concepts of 3D ICs and 2.5D ICs. Prior work on testing of 2.5D ICs is studied. An efficient method is presented to locate defects in a passive interposer before stacking. The proposed test architecture uses e-fuses that can be programmed to connect or disconnect functional paths inside the interposer. The concept of a die footprint is utilized for interconnect testing, and the overall assembly and test flow is described. Moreover, the concept of weighted critical area is defined and utilized to reduce test time. In order to fully determine the location of each e-fuse and the order of functional interconnects in a test path, we also present a test-path design algorithm. The proposed algorithm can generate all test paths for interconnect testing.

In order to test for opens, shorts, and interconnect delay defects in the interposer, a test architecture is proposed that is fully compatible with the IEEE 1149.1 standard and relies on an enhancement of the standard test access port (TAP) controller. To reduce test cost, a test-path design and scheduling technique is also presented that minimizes a composite cost function based on test time and the design-for-test (DfT) overhead in terms of additional through silicon vias (TSVs) and micro-bumps needed for test access. The locations of the dies on the interposer are taken into consideration in order to determine the order of dies in a test path.

To address the scenario of high density of I/O ports and interconnects, an efficient built-in self-test (BIST) technique is presented that targets the dies and the interposer interconnects. The proposed BIST architecture can be enabled by the standard TAP controller in the IEEE 1149.1 standard. The area overhead introduced by this BIST architecture is negligible; it includes two simple BIST controllers, a linear-feedback-shift-register (LFSR), a multiple-input-signature-register (MISR), and some extensions to the boundary-scan cells in the dies on the interposer. With these extensions, all boundary-scan cells can be used for self-configuration and self-diagnosis during interconnect testing. To reduce the overall test cost, a test scheduling and optimization technique under power constraints is described.

In order to accomplish testing with a small number test pins, the dissertation presents two efficient ExTest scheduling strategies that implements interconnect testing between tiles inside an system on chip (SoC) die on the interposer while satisfying the practical constraint that the number of required test pins cannot exceed the number of available pins at the chip level. The tiles in the SoC are divided into groups based on the manner in which they are interconnected. In order to minimize the test time, two optimization solutions are introduced. The first solution minimizes the number of input test pins, and the second solution minimizes the number output test pins. In addition, two subgroup configuration methods are further proposed to generate subgroups inside each test group.

Finally, the dissertation presents a programmable method for shift-clock stagger assignment to reduce power supply noise during SoC die testing in 2.5D ICs. An SoC die in the 2.5D IC is typically composed of several blocks and two neighboring blocks that share the same power rails should not be toggled at the same time during shift. Therefore, the proposed programmable method does not assign the same stagger value to neighboring blocks. The positions of all blocks are first analyzed and the shared boundary length between blocks is then calculated. Based on the position relationships between the blocks, a mathematical model is presented to derive optimal result for small-to-medium sized problems. For larger designs, a heuristic algorithm is proposed and evaluated.

In summary, the dissertation targets important design and optimization problems related to testing of interposer-based 2.5D ICs. The proposed research has led to theoretical insights, experiment results, and a set of test and design-for-test methods to make testing effective and feasible from a cost perspective.

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Empirical studies of education programs and systems, by nature, rely upon use of student outcomes that are measurable. Often, these come in the form of test scores. However, in light of growing evidence about the long-run importance of other student skills and behaviors, the time has come for a broader approach to evaluating education. This dissertation undertakes experimental, quasi-experimental, and descriptive analyses to examine social, behavioral, and health-related mechanisms of the educational process. My overarching research question is simply, which inside- and outside-the-classroom features of schools and educational interventions are most beneficial to students in the long term? Furthermore, how can we apply this evidence toward informing policy that could effectively reduce stark social, educational, and economic inequalities?

The first study of three assesses mechanisms by which the Fast Track project, a randomized intervention in the early 1990s for high-risk children in four communities (Durham, NC; Nashville, TN; rural PA; and Seattle, WA), reduced delinquency, arrests, and health and mental health service utilization in adolescence through young adulthood (ages 12-20). A decomposition of treatment effects indicates that about a third of Fast Track’s impact on later crime outcomes can be accounted for by improvements in social and self-regulation skills during childhood (ages 6-11), such as prosocial behavior, emotion regulation and problem solving. These skills proved less valuable for the prevention of mental and physical health problems.

The second study contributes new evidence on how non-instructional investments – such as increased spending on school social workers, guidance counselors, and health services – affect multiple aspects of student performance and well-being. Merging several administrative data sources spanning the 1996-2013 school years in North Carolina, I use an instrumental variables approach to estimate the extent to which local expenditure shifts affect students’ academic and behavioral outcomes. My findings indicate that exogenous increases in spending on non-instructional services not only reduce student absenteeism and disciplinary problems (important predictors of long-term outcomes) but also significantly raise student achievement, in similar magnitude to corresponding increases in instructional spending. Furthermore, subgroup analyses suggest that investments in student support personnel such as social workers, health services, and guidance counselors, in schools with concentrated low-income student populations could go a long way toward closing socioeconomic achievement gaps.

The third study examines individual pathways that lead to high school graduation or dropout. It employs a variety of machine learning techniques, including decision trees, random forests with bagging and boosting, and support vector machines, to predict student dropout using longitudinal administrative data from North Carolina. I consider a large set of predictor measures from grades three through eight including academic achievement, behavioral indicators, and background characteristics. My findings indicate that the most important predictors include eighth grade absences, math scores, and age-for-grade as well as early reading scores. Support vector classification (with a high cost parameter and low gamma parameter) predicts high school dropout with the highest overall validity in the testing dataset at 90.1 percent followed by decision trees with boosting and interaction terms at 89.5 percent.

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Advancement in correction or palliation of congenital cardiac lesions has greatly improved the lifespan of congenital heart disease patients, resulting in a rapidly growing adult congenital heart disease (ACHD) population. As this group has increased in number and age, emerging science has highlighted the systemic nature of ACHD. Providers caring for these patients are tasked with long-term management of multiple neurologic, pulmonary, hepatic, renal, and endocrine manifestations that arise as syndromic associations with congenital heart defects or as sequelae of primary structural or hemodynamic abnormalities. In this review, we outline the current understanding and recent research into these extra-cardiac manifestations.

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Natural and man-made disasters have gained attention at all levels of policy-making in recent years. Emergency management tasks are inherently complex and unpredictable, and often require coordination among multiple organizations across different levels and locations. Effectively managing various knowledge areas and the organizations involved has become a critical emergency management success factor. However, there is a general lack of understanding about how to describe and assess the complex nature of emergency management tasks and how knowledge integration can help managers improve emergency management task performance. The purpose of this exploratory research was first, to understand how emergency management operations are impacted by tasks that are complex and inter-organizational and second, to investigate how knowledge integration as a particular knowledge management strategy can improve the efficiency and effectiveness of the emergency tasks. Three types of specific knowledge were considered: context-specific, technology-specific, and context-and-technology-specific. The research setting was the Miami-Dade Emergency Operations Center (EOC) and the study was based on the survey responses from the participants in past EOC activations related to their emergency tasks and knowledge areas. The data included task attributes related to complexity, knowledge area, knowledge integration, specificity of knowledge, and task performance. The data was analyzed using multiple linear regressions and path analyses, to (1) examine the relationships between task complexity, knowledge integration, and performance, (2) the moderating effects of each type of specific knowledge on the relationship between task complexity and performance, and (3) the mediating role of knowledge integration. As per theory-based propositions, the results indicated that overall component complexity and interactive complexity tend to have a negative effect on task performance. But surprisingly, procedural rigidity tended to have a positive effect on performance in emergency management tasks. Also as per our expectation, knowledge integration had a positive relationship with task performance. Interestingly, the moderating effects of each type of specific knowledge on the relationship between task complexity and performance were varied and the extent of mediation of knowledge integration depended on the dimension of task complexity.

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El arteterapia permite una aproximación creativa biográfica particularmente valiosa en la etapa final de la vida. La persona enferma presenta múltiples necesidades – físicas, emocionales, sociales y espirituales – que solo una atención holística puede pretender abarcar, tal como lo contempla la filosofía de los cuidados paliativos. El arteterapeuta integrado en el equipo interdisciplinar contribuye a aliviar y acompañar el sufrimiento del paciente y su familia. Se presentan aquí las bases teóricas y la metodología de la intervención, así como el marco sanitario en el cual se inscribe.

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The current study builds upon a previous study, which examined the degree to which the lexical properties of students’ essays could predict their vocabulary scores. We expand on this previous research by incorporating new natural language processing indices related to both the surface- and discourse-levels of students’ essays. Additionally, we investigate the degree to which these NLP indices can be used to account for variance in students’ reading comprehension skills. We calculated linguistic essay features using our framework, ReaderBench, which is an automated text analysis tools that calculates indices related to linguistic and rhetorical features of text. University students (n = 108) produced timed (25 minutes), argumentative essays, which were then analyzed by ReaderBench. Additionally, they completed the Gates-MacGinitie Vocabulary and Reading comprehension tests. The results of this study indicated that two indices were able to account for 32.4% of the variance in vocabulary scores and 31.6% of the variance in reading comprehension scores. Follow-up analyses revealed that these models further improved when only considering essays that contained multiple paragraph (R2 values = .61 and .49, respectively). Overall, the results of the current study suggest that natural language processing techniques can help to inform models of individual differences among student writers.

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Over the last thirty years, there has been an increased demand for better management of public sector organisations (PSOs). This requires that they are answerable for the inputs that they are given but also for what they achieve with these inputs (Hood 1991; Hood 1995). It is suggested that this will improve the management of the organisation through better planning and control, and the achievement of greater accountability (Smith 1995). However, such a rational approach with clear goals and the means to measure achievement can cause difficulties for many PSOs. These difficulties include the distinctive nature of the public sector due to the political environment within which the public sector manager operates (Stewart and Walsh 1992) and the fact that PSOs will have many stakeholders, each of whom will have their own specific objectives based on their own perspective (Boyle 1995). This can
result in goal ambiguity which means that there is leeway in interpreting the results of the PSO. The National Asset Management Agency (NAMA) was set up to bring stability to the financial system by buying loans from the banks (which were in most cases, non-performing loans). The intention was to cleanse the banks of these loans so that they could return to their normal business of taking deposits and making loans. However, the legislation, also gave NAMA a wide range of other responsibilities including responsibility for facilitating credit in the economy and protecting the interests of taxpayers. In more recent times, NAMA has been given responsibility for building social housing. This wide-range of activities is a clear example of a PSO being given multiple goals which may conflict and is therefore likely to lead to goal ambiguity. This makes it very difficult to evaluate NAMA’s performance as they are attempting to meet numerous goals at the same time and also highlights the complexity of policy making in the public sector. The purpose of this paper is to examine how NAMA dealt with goal ambiguity. This will be done through a thematic analysis of its annual reports over the last five years. The paper’s will contribute to the ongoing debate about the evaluation of PSOs and the complex environment within which they operate which makes evaluation difficult as they are
answerable to multiple stakeholders who have different objectives and different criteria for measuring success.

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This paper analyzes the impact of transceiver impairments on outage probability (OP) and throughput of decode-and-forward two-way cognitive relay (TWCR) networks, where the relay is self-powered by harvesting energy from the transmitted signals. We consider two bidirectional relaying protocols namely, multiple access broadcast (MABC) protocol and time division broadcast (TDBC) protocol, as well as, two power transfer policies namely, dual-source (DS) energy transfer and single-fixed-source (SFS) energy transfer. Closed-form expressions for OP and throughput of the network are derived in the context of delay-limited transmission. Numerical results corroborate our analysis, thereby we can quantify the degradation of OP and throughput of TWCR networks due to transceiver hardware impairments. Under the specific parameters, our results indicate that the MABC protocol achieves asymptotically a higher throughput by 0.65 [bits/s/Hz] than the TDBC protocol, while the DS energy transfer scheme offers better performance than the SFS policy for both relaying protocols.

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MENDES, Jean Joubert Freitas. Renovando os sentidos: percepção e escrita etnográfica na etnomusicologia. In: ANPPOM, 17. Rio de Janeiro, 2005. Anais... Rio de Janeiro: UFRN/ANPPOM, 2005.

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Thesis (Ph.D.)--University of Washington, 2016-07

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This study examines the complex hotel buyer decision process in front of the tourism distribution channels. Its objective is to describe the influence level of the tourism marketing intermediaries, mainly the travel agents and tour operators, over the hotel decision process by the buyer-tourist. The data collection process was done trough a survey with three hundred brazilian tourists hosted in nineteen hotels of Natal, capital of Rio Grande do Norte, Brazil. The data analysis was done using some multivariate statistic techniques as correlation analysis, multiple regression analysis, factor analysis and multiple discriminant analysis. The research characterizes the hotel services consumers profile and his trip, and identifying the distribution channels used by them. Furthermore, the research verifies the intermediaries influence exercised over hotel buyer decision process, looking for identify causality relations between the influence level and the buyer profile. Verifies that information about hotels available on internet reduces the probability that this influence can be practiced; however it was possible identifying those consumers considers this information complementary and non-substitutes than the information from intermediaries. The characteristics of the data do not allow indentifying the factors that constraint the intermediaries influence neither identifying discriminant functions of the specific distribution channel choice by consumers. The study concludes that consumers don t agree in have been influenced by intermediaries or don t know if they have, still considering important to consult them and internet doesn t substitute their function as information source

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L’ingénierie des biomatériaux a connu un essor prodigieux ces dernières décennies passant de matériaux simples à des structures plus complexes, particulièrement dans le domaine cardiovasculaire. Cette évolution découle de la nécessité des biomatériaux de permettre la synergie de différentes propriétés, dépendantes de leurs fonctions, qui ne sont pas forcément toutes compatibles. Historiquement, les premiers matériaux utilisés dans la conception de dispositifs médicaux étaient ceux présentant le meilleur compromis entre les propriétés physico-chimiques, mécaniques et biologiques que nécessitait leur application. Cependant, il se peut qu’un tel dispositif possède les bonnes propriétés physico-chimiques ou mécaniques, mais que sa biocompatibilité soit insuffisante induisant ainsi des complications cliniques. Afin d’améliorer ces propriétés biologiques tout en conservant les propriétés de volume du matériau, une solution est d’en modifier la surface. L’utilisation d’un revêtement permet alors de moduler la réponse biologique à l’interface biomatériau-hôte et de diminuer les effets indésirables. Ces revêtements sont optimisés selon deux critères principaux : la réponse biologique et la réponse mécanique. Pour la réponse biologique, les deux approches principales sont de mettre au point des revêtements proactifs qui engendrent l’adhérence, la prolifération ou la migration cellulaire, ou passifs, qui, principalement, sont inertes et empêchent l’adhérence de composés biologiques. Dans certains cas, il est intéressant de pouvoir favoriser certaines cellules et d’en limiter d’autres, par exemple pour lutter contre la resténose, principalement due à la prolifération incontrôlée de cellules musculaires lisses qui conduit à une nouvelle obstruction de l’artère, suite à la pose d’un stent. La recherche sur les revêtements de stents vise, alors, à limiter la prolifération de ces cellules tout en facilitant la ré-endothélialisation, c’est-à-dire en permettant l’adhérence et la prolifération de cellules endothéliales. Dans d’autres cas, il est intéressant d’obtenir des surfaces limitant toute adhérence cellulaire, comme pour l’utilisation de cathéter. Selon leur fonction, les cathéters doivent empêcher l’adhérence cellulaire, en particulier celle des bactéries provoquant des infections, et être hémocompatibles, principalement dans le domaine vasculaire. Il a été démontré lors d’études précédentes qu’un copolymère à base de dextrane et de poly(méthacrylate de butyle) (PBMA) répondait aux problématiques liées à la resténose et qu’il possédait, de plus, une bonne élasticité, propriété mécanique importante due à la déformation que subit le stent lors de son déploiement. L’approche de ce projet était d’utiliser ce copolymère comme revêtement de stents et d’en améliorer l’adhérence à la surface en formant des liens covalents avec la surface. Pour ce faire, cela nécessitait l’activation de la partie dextrane du copolymère afin de pouvoir le greffer à la surface aminée. Il était important de vérifier pour chaque étape l’influence des modifications effectuées sur les propriétés biologiques et mécaniques des matériaux obtenus, mais aussi d’un point de vue de la chimie, l’influence que cette modification pouvait induire sur la réaction de copolymérisation. Dans un premier temps, seul le dextrane est considéré et est modifié par oxydation et carboxyméthylation puis greffé à des surfaces fluorocarbonées aminées. L’analyse physico-chimique des polymères de dextrane modifiés et de leur greffage permet de choisir une voie de modification préférentielle qui n’empêchera pas ultérieurement la copolymérisation. La carboxyméthylation permet ainsi d’obtenir un meilleur recouvrement de la surface tout en conservant la structure polysaccharidique du dextrane. Le greffage du dextrane carboxyméthylé (CMD) est ensuite optimisé selon différents degrés de modification, tenant compte aussi de l’influence que ces modifications peuvent induire sur les propriétés biologiques. Finalement, les CMD précédemment étudiés, avec des propriétés biologiques définies, sont copolymérisés avec des monomères de méthacrylate de butyle (BMA). Les copolymères ainsi obtenus ont été ensuite caractérisés par des analyses physico-chimiques, biologiques et mécaniques. Des essais préliminaires ont montrés que les films de copolymères étaient anti-adhérents vis-à-vis des cellules, ce qui a permis de trouver de nouvelles applications au projet. Les propriétés élastiques et anti-adhérentes présentées par les films de copolymères CMD-co-PBMA, les rendent particulièrement intéressants pour des applications comme revêtements de cathéters.

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L’endométriose est une maladie gynécologique, touchant les femmes en âge de procréer. Cette pathologie est caractérisée par la présence de tissu endométrial ectopique, c’est-à-dire en dehors de la cavité utérine. Des dysfonctions du système immunitaire sont de plus en plus souvent suspectées comme étant un des éléments responsables de la pathogenèse de cette maladie. L’objectif général de ce projet a donc été d’étudier les mécanismes cellulaires de molécules pro-inflammatoires aux propriétés variées et à l’expression anormalement élevée dans cette pathologie, que sont MIF et les prostaglandines PGE2 et PGF2α, dans les anomalies inflammatoires et invasives en cause dans cette pathologie. La première partie de nos travaux a porté sur l’étude d’un modèle murin de l’endométriose déficient du gène MIF. Le nombre et le volume des lésions collectées à partir des souris déficientes pour le gène MIF sont significativement inférieurs à ceux mesurés dans des souris sauvages utilisées comme contrôle. L’analyse par PCR des cellules isolées des lésions de souris déficientes du gène MIF a révélé une expression réprimée des protéines d’adhésion, d’inflammation et d’angiogenèse. Ces données démontrent pour la première fois que le MIF agit directement sur la croissance et la progression de lésions d’endométriose in vivo. Une partie de nos travaux a porté sur les molécules nécessaires au métabolisme de PGE2 et PGF2α dans l’endomètre eutopique des femmes normales et l’endomètre eutopique et ectopique des femmes atteintes d’endométriose. Selon nos données, l’expression de certains de ces facteurs est perturbée durant cette maladie, ce qui peut avoir des effets délétères sur la physiologie de la procréation. La stimulation des cellules ectopiques par PGF2α entraîne une libération accrue de VEGF et CXCL-8, ceci via l’induction de COX-2 et des deux variants d’épissage du récepteur FP. De plus, la PKC joue un rôle dans ce phénomène, dépendamment et indépendamment de la PLC. Par son effet inducteur sur la libération de VEGF et CXCL-8, PGF2α pourrait favoriser l’aspect inflammatoire et le développement ectopique des lésions d’endométriose, notamment par des phénomènes d’angiogenèse et de prolifération cellulaire accrus. L’effet de PGF2α sur la libération de VEGF et CXCL-8 par les cellules endométriales ectopiques pourrait également expliquer les quantités élevées de ces cytokines dans le liquide péritonéal des femmes atteintes d’endométriose, un phénomène suspecté dans l’infertilité et les douleurs associées à cette maladie. Nos derniers résultats obtenus à partir du liquide péritonéal montrent un profil cytokinique en faveur de l’angiogenèse et la prolifération des lésions d’endométriose, avec une forte augmentation des facteurs suivants : EGF, FGF-2, IL-1α, MIP-1β, TGFα, PDGF-AA, PDGF-BB, MCP-3, sCD40L, Gro Pan, IL-17α, MDC et Rantes, confortant nos observations préalables redéfinissant la maladie comme étant d’origine angio-inflammatoire. L’endométriose et ses symptômes sont des phénomènes complexes ayant probablement plus qu’une seule origine. Parmi les nombreux facteurs à l’expression altérée dans l’endométriose, notre étude montre que MIF, PGE2 et PGF2α, ainsi qu’une pléthore de facteurs pro-angiogéniques pourraient être de ceux jouant un rôle dans l’infertilité et les douleurs reliées à cette maladie.

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Partnership is a dominant theme in education policy and practice in England and in other western countries but remains relatively under-researched, especially with respect to what sustains a partnership. This article draws on a study of partnership working in the field of post-16 learning that revealed the role of dimensions of social capital in supporting and sustaining the case study partnership. The research adopted a grounded approach and used multiple methods of data gathering including observations of partnership meetings, semi-structured interviews and documentary research. The findings reported here focus on aspects of partnership working and facets of social capital that support and sustain partnership, including multiple layers of collaboration, networks and networking, high levels of trust and shared norms and values amongst key participants. The analysis suggests that the contested concept of social capital provides a useful theoretical frame for understanding the basis of sustainability in education partnerships.

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MENDES, Jean Joubert Freitas. Renovando os sentidos: percepção e escrita etnográfica na etnomusicologia. In: ANPPOM, 17. Rio de Janeiro, 2005. Anais... Rio de Janeiro: UFRN/ANPPOM, 2005.