645 resultados para REGULARITY LEMMA


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The lamination and burrowing patterns in 17 box cores were analyzed with the aid of X-ray photographs and thin sections. A standardized method of log plotting made statistical analysis of the data possible. Several 'structure types' were established, although it was realized that the boundaries are purely arbitrary divisions in what can sometimes be a continuous sequence. In the transition zone between marginal sand facies and fine-grained basin facies, muddy sediment is found which contains particularly well differentiated, alternating laminae. This zone is also characterized by layers rich in plant remains. The alternation of laminae shows a high degree of statistical scattering. Even though a small degree of cyclic periodicity could be defined, it was impossible to correlate individual layers from core to core across the bay. However, through a statistical handling of the plots, zones could be separated on the basis of the number of sand layers they contained. These more or minder sandy zones clarified the bottom reflections seen in the records of the echograph from the area. The manner of facies change across the bay, suggests that no strong bottom currents are effective in the Eckernförde Bay. The marked asymmetry between the north and south flanks of the profile can be attributed to the stronger action of waves on the more exposed areas. Grain size analyses were made from the more homogeneous units found in a core from the transition-facies zone. The results indicate that the most pronounced differences between layers appear in the silt range, and although the differences are slight, they are statistically significant. Layers rich in plant remains were wet-sieved in order to separate the plant detritus. This was than analyzed in a sediment settling balance and found to be hydrodynamically equivalent to a well-sorted, finegrained sand. A special, rhythmic cross-bedding type with dimensions in the millimeter range, has been named 'Crypto-cross-lamination' and is thought to represent rapid sedimentation in an area where only very weak bottom currents are present. It is found only in the deepest part of the basin. Relatively large sand grains, scattered within layers of clayey-silty matrix, seem to be transported by flotation. Thin section examination showed that the inner part of Eckernförder Bay carbonate grains (e. g. Foraminifera shells) were preserved throughout the cores, while in the outer part of the bay they were not present. Well defined tracks and burrows are relatively rare in all of the facies in comparision to the generally strongly developed deformation burrowing. The application of special measures for the deformation burrowing allowed to plot their intensity in profile for each core. A degree of regularity could be found in these burrowing intensity plots, with higher values appearing in the sandy facies, but with no clear differences between sand and silt layers in the transition facies. Small sections in the profiles of the deepest part of the bay show no bioturbation at all.

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This paper reports the findings from a study of the learning of English intonation by Spanish speakers within the discourse mode of L2 oral presentation. The purpose of this experiment is, firstly, to compare four prosodic parameters before and after an L2 discourse intonation training programme and, secondly, to confirm whether subjects, after the aforementioned L2 discourse intonation training, are able to match the form of these four prosodic parameters to the discourse-pragmatic function of dominance and control. The study designed the instructions and tasks to create the oral and written corpora and Brazil’s Pronunciation for Advanced Learners of English was adapted for the pedagogical aims of the present study. The learners’ pre- and post-tasks were acoustically analysed and a pre / post- questionnaire design was applied to interpret the acoustic analysis. Results indicate most of the subjects acquired a wider choice of the four prosodic parameters partly due to the prosodically-annotated transcripts that were developed throughout the L2 discourse intonation course. Conversely, qualitative and quantitative data reveal most subjects failed to match the forms to their appropriate pragmatic functions to express dominance and control in an L2 oral presentation.

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Informatie wordt gegeven over de beleidsvraag, de probleemopzet, het onderzoeksontwerp met kernvariabelelen, het onderzoeksproces en de belangrijkste uitkomsten van deze multiniveau, longitudinale veiligheidsmonitor. Tenslotte worden enkele van de meest kenmerkende aspecten van deze onderzoeksmethode behandeld.

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Major food adulteration and contamination events occur with alarming regularity and are known to be episodic, with the question being not if but when another large-scale food safety/integrity incident will occur. Indeed, the challenges of maintaining food security are now internationally recognised. The ever increasing scale and complexity of food supply networks can lead to them becoming significantly more vulnerable to fraud and contamination, and potentially dysfunctional. This can make the task of deciding which analytical methods are more suitable to collect and analyse (bio)chemical data within complex food supply chains, at targeted points of vulnerability, that much more challenging. It is evident that those working within and associated with the food industry are seeking rapid, user-friendly methods to detect food fraud and contamination, and rapid/high-throughput screening methods for the analysis of food in general. In addition to being robust and reproducible, these methods should be portable and ideally handheld and/or remote sensor devices, that can be taken to or be positioned on/at-line at points of vulnerability along complex food supply networks and require a minimum amount of background training to acquire information rich data rapidly (ergo point-and-shoot). Here we briefly discuss a range of spectrometry and spectroscopy based approaches, many of which are commercially available, as well as other methods currently under development. We discuss a future perspective of how this range of detection methods in the growing sensor portfolio, along with developments in computational and information sciences such as predictive computing and the Internet of Things, will together form systems- and technology-based approaches that significantly reduce the areas of vulnerability to food crime within food supply chains. As food fraud is a problem of systems and therefore requires systems level solutions and thinking.

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Inverse simulations of musculoskeletal models computes the internal forces such as muscle and joint reaction forces, which are hard to measure, using the more easily measured motion and external forces as input data. Because of the difficulties of measuring muscle forces and joint reactions, simulations are hard to validate. One way of reducing errors for the simulations is to ensure that the mathematical problem is well-posed. This paper presents a study of regularity aspects for an inverse simulation method, often called forward dynamics or dynamical optimization, that takes into account both measurement errors and muscle dynamics. The simulation method is explained in detail. Regularity is examined for a test problem around the optimum using the approximated quadratic problem. The results shows improved rank by including a regularization term in the objective that handles the mechanical over-determinancy. Using the 3-element Hill muscle model the chosen regularization term is the norm of the activation. To make the problem full-rank only the excitation bounds should be included in the constraints. However, this results in small negative values of the activation which indicates that muscles are pushing and not pulling. Despite this unrealistic behavior the error maybe small enough to be accepted for specific applications. These results is a starting point start for achieving better results of inverse musculoskeletal simulations from a numerical point of view.

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Cette thèse développe des méthodes bootstrap pour les modèles à facteurs qui sont couram- ment utilisés pour générer des prévisions depuis l'article pionnier de Stock et Watson (2002) sur les indices de diffusion. Ces modèles tolèrent l'inclusion d'un grand nombre de variables macroéconomiques et financières comme prédicteurs, une caractéristique utile pour inclure di- verses informations disponibles aux agents économiques. Ma thèse propose donc des outils éco- nométriques qui améliorent l'inférence dans les modèles à facteurs utilisant des facteurs latents extraits d'un large panel de prédicteurs observés. Il est subdivisé en trois chapitres complémen- taires dont les deux premiers en collaboration avec Sílvia Gonçalves et Benoit Perron. Dans le premier article, nous étudions comment les méthodes bootstrap peuvent être utilisées pour faire de l'inférence dans les modèles de prévision pour un horizon de h périodes dans le futur. Pour ce faire, il examine l'inférence bootstrap dans un contexte de régression augmentée de facteurs où les erreurs pourraient être autocorrélées. Il généralise les résultats de Gonçalves et Perron (2014) et propose puis justifie deux approches basées sur les résidus : le block wild bootstrap et le dependent wild bootstrap. Nos simulations montrent une amélioration des taux de couverture des intervalles de confiance des coefficients estimés en utilisant ces approches comparativement à la théorie asymptotique et au wild bootstrap en présence de corrélation sérielle dans les erreurs de régression. Le deuxième chapitre propose des méthodes bootstrap pour la construction des intervalles de prévision permettant de relâcher l'hypothèse de normalité des innovations. Nous y propo- sons des intervalles de prédiction bootstrap pour une observation h périodes dans le futur et sa moyenne conditionnelle. Nous supposons que ces prévisions sont faites en utilisant un ensemble de facteurs extraits d'un large panel de variables. Parce que nous traitons ces facteurs comme latents, nos prévisions dépendent à la fois des facteurs estimés et les coefficients de régres- sion estimés. Sous des conditions de régularité, Bai et Ng (2006) ont proposé la construction d'intervalles asymptotiques sous l'hypothèse de Gaussianité des innovations. Le bootstrap nous permet de relâcher cette hypothèse et de construire des intervalles de prédiction valides sous des hypothèses plus générales. En outre, même en supposant la Gaussianité, le bootstrap conduit à des intervalles plus précis dans les cas où la dimension transversale est relativement faible car il prend en considération le biais de l'estimateur des moindres carrés ordinaires comme le montre une étude récente de Gonçalves et Perron (2014). Dans le troisième chapitre, nous suggérons des procédures de sélection convergentes pour les regressions augmentées de facteurs en échantillons finis. Nous démontrons premièrement que la méthode de validation croisée usuelle est non-convergente mais que sa généralisation, la validation croisée «leave-d-out» sélectionne le plus petit ensemble de facteurs estimés pour l'espace généré par les vraies facteurs. Le deuxième critère dont nous montrons également la validité généralise l'approximation bootstrap de Shao (1996) pour les regressions augmentées de facteurs. Les simulations montrent une amélioration de la probabilité de sélectionner par- cimonieusement les facteurs estimés comparativement aux méthodes de sélection disponibles. L'application empirique revisite la relation entre les facteurs macroéconomiques et financiers, et l'excès de rendement sur le marché boursier américain. Parmi les facteurs estimés à partir d'un large panel de données macroéconomiques et financières des États Unis, les facteurs fortement correlés aux écarts de taux d'intérêt et les facteurs de Fama-French ont un bon pouvoir prédictif pour les excès de rendement.

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[EN]In recent years, several historical rock art sites have been located in Alcazar de San. Given its fragility, one of the most important and urgent tasks being undertaken within the framework of the DIPAR research project is the documentation of these sites. Among the various techniques used to this, two stand out above the rest: the application of digital photography at night, and three-dimensional documentation.

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In questa tesi si presenta il concetto di politopo convesso e se ne forniscono alcuni esempi, poi si introducono alcuni metodi di base e risultati significativi della teoria dei politopi. In particolare si dimostra l'equivalenza tra le due definizioni di H-politopo e di V-politopo, sfruttando il metodo di eliminazione di Fourier-Motzkin per coni. Tutto ciò ha permesso di descrivere, grazie al lemma di Farkas, alcune importanti costruzioni come il cono di recessione e l'omogeneizzazione di un insieme convesso.

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To present research had for objective to study the quality of the employment in the maturation Laboratories and larviculture of the Beach of Barreta/RN, adopting for so much the criteria used by Reinecke(1999) to characterize a quality employment: surrender, benefits non salary, regularity and work reliability and of the wage, contractual status, social protection, work day, intensity of the work, risk of accidents and of occupational diseases, involvement in linked decisions to the section work, possibility for the development of professional qualifications. Of the exam of the data it was verified that the generated employments are considered employments of good quality. However, this result should be analyzed to the light of a context of extreme informality and of precarization of the work. Therefore, the results should be relativized. He/she/you imports to retain that one of the limitations of the study resides in the impossibility of generalizing the data for the whole section of the sea carcinicultura. In spite of that fact, he/she is considered that the objectives of the research were assisted fully and that the characterization of the profile of the employment generated by the section of the shrimpculture it is extremely important for the drawing of public politics gone back to foment this activity.

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We consider a (p, q)− equation (1 < q < p, p ≥ 2) with a parametric concave term and a (p − 1)− linear perturbation. We show that the problem have five nontrivial smooth solutions: four of constant sign and the fifth nodal. When q = 2 (i.e., (p, 2) equation) we show that the problem has six nontrivial smooth solutions, but we do not specify the sign of the sixth solution. Our approach uses variational methods, together with truncation and comparison techniques and Morse theory.

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The evaluation of public policies that promote Food Security and Nutrition (FSN) it s a multidisciplinary activity extremely relevant to the effectiveness of actions to legitimize the Human Right to Adequate Food (HRAF). This study aimed at assessing the effectiveness of the unit project Natal-RN Café do Trabalhador in promoting SAN to its users. The theoretical framework is based on the public and political and on the dimensions of the concept of FSN (quantity and quality-regularity). Through a qualitative approach, methodologically this was the work of an evaluation of efficiency of the unit Natal-RN of Café do Trabalhador project in light of the assumptions of the concept of SAN. Data collection was conducted through retrospective archival research in official documents of the project, semi-structured interviews with managers involved in its implementation (representative of the Secretary of State for Employment, Housing and Care of RN SETHAS and third party), socioeconomic questionnaire applied to the users of the unit, check the amount, regularity and quality of meals offered for 15 days (menu routine) using the descriptive form menu and form filling type checklist for verification of compliance with good practices . Methods of analysis, we used content analysis, descriptive statistics and compared to previously established parameters for the project. As categories of analysis were defined organizational arrangement, access, user, food quantity-regularity and food quality. The results show that, it was found in the category arrangement that will implement the project dismissed technical criteria for choosing the districts and the quantitative distribution of meals for each location. It was found that the valuation of the shares of the company outsources technical SETHA has not been performed. We observed in the access category, the unit has a strategic location, but lack of space in the refectory. The main obstacle to economic access for users is the lack of a register for the beneficiaries. In the category of users, it was identified that the clientele of the project it is predominantly men, with more than 51 years, low education, earning wages less 1 obtained through informal employment, which they move up through the unit transport collective, go to all days of operation due primarily to price. About the meals category quantity-regularity of food showed that the menu serves 95% of the desired needs, and that holidays and weekends are periods of disrupting the regularity of supply of meals. Regarding the category of food quality, it was found that the nutritional aspect on the menu are food sources rich in sodium, nitrates and low in fiber. In the aspect of hygiene and sanitation are the main limitations related to waste management, lack of exposure controls of food prepared and inadequacies of the physical structure. The results showed that in general and the institutional arrangement of the organs attached to the project should establish a systematic evaluation project is to establish as a promoter of and FSN overcome these obstacles

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A prática regular e bem orientada da atividade física (AF) na 3ª idade possui diversos benefícios na saúde mas para que tal aconteça, é necessária a existência de um PAF que seja desenvolvido por um profissional que conheça as limitações próprias desta idade e que direcione o programa especificamente para este público-alvo. Pretende-se com este estudo caraterizar os Programas de Atividade Física (PAF) inseridos nos diferentes contextos institucionais e se o impacto que têm é percecionado do mesmo modo por utentes e técnicos. A amostra é composta por 27 pessoas: 16 pessoas idosas institucionalizadas e 11 técnicos que conceberam ou dinamizam os PAF. Os dados foram recolhidos através da aplicação de entrevistas, realização de observação das aulas de ginástica e análise de documentos fornecidos pelas instituições Verificou-se que a participação nos PAF é feita essencialmente por utentes do sexo feminino. Os profissionais que coordenam ou dinamizam os PAF também são essencialmente mulheres. Os programas existentes têm estruturas, objetivos e atividades semelhantes. A avaliação inicial dos participantes é realizada na maioria dos PAF; a interna acontece em poucas instituições, também, e junto dos participantes só são utilizadas folhas de presença. Os PAF são totalmente gratuitos para os seus utentes. Apesar de os PAF pertencerem a contextos institucionais diferentes, no geral, seguem uma estrutura lógica e bem concebida. A AF deverá ser vista como mais do que um momento lúdico e para tal aconteça, as instituições que a desenvolvem, devem promover e aumentar a sua regularidade

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A proposta deste artigo foi estudar a evolução do tamanho das cidades dos estados do nordeste do Brasil para os anos de 1990, 2000 e 2010 através da regularidade empírica conhecida como lei de Zipf, a qual pode ser representada por meio da distribuição de Pareto. Por meio da análise na dinâmica da distribuição das populações através do tempo, o crescimento urbano revelou uma persistência hierárquica das cidades de Salvador, Fortaleza e Recife, enquanto que São Luís experimentou o quarto lugar no rankinging das maiores cidades, que persistiu nas duas últimas décadas. A lei de Zipf não se verificou quando se considerou as cidades do Nordeste em conjunto, que pode ser devido ao menor grau de desenvolvimento urbano das cidades dessa região. Na análise dos estados em separado, também não se observou a lei de Zipf, embora tenha se verificado a lei de Gibrat, a qual postula que o crescimento das cidades é independente de seu tamanho. Por fim, acredita-se que a instalação do complexo minerometalúrgico do Maranhão tenha contribuído para o desenvolvimento e para a redução da desigualdade urbana intracidade nesta área.

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Improvements in diagnostic techniques and, above all, breast cancer screening campaigns - essential for early diagnosis - have enabled the objectives of conservative surgery to be pursued: disease control, no or low incidence of recurrences and an excellent esthetic result. However, to reach these objectives, it is essential to ensure a careful evaluation of the medical history of every patient, a detailed clinical examination and the correct interpretation of imaging. Particular attention should be paid to all factors influencing the choice of treatment and/or possible local recurrence: age, site, tumor volume, genetic predisposition, pregnancy, previous radiotherapy, pathological features, and surgical margins. The decision to undertake conservative treatment thus requires a multidisciplinary approach involving pathologists, surgeons and oncological radiologists, as well, of course, as the patient herself.

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The authors describe the case of a patient with two particularly rare contiguous tumors, myofibroblastoma and osteosarcoma, in the same breast. Rare does not mean untreatable, and the chance of recovery is no less than with more common tumors. However, rare tumors do present a significant problem for pathologists due to diagnostic difficulties, and so an exact prognosis is not always possible.