Shock Train/Boundary-Layer Interaction in Rectangular Scramjet Isolators

Numerous studies of the dual-mode scramjet isolator, a critical component in preventing inlet unstart and/or vehicle loss by containing a collection of flow disturbances called a shock train, have been performed since the dual-mode propulsion cycle was introduced in the 1960s. Low momentum corner flow and other three-dimensional effects inherent to rectangular isolators have, however, been largely ignored in experimental studies of the boundary layer separation driven isolator shock train dynamics. Furthermore, the use of two dimensional diagnostic techniques in past works, be it single-perspective line-of-sight schlieren/shadowgraphy or single axis wall pressure measurements, have been unable to resolve the three-dimensional flow features inside the rectangular isolator. These flow characteristics need to be thoroughly understood if robust dual-mode scramjet designs are to be fielded. The work presented in this thesis is focused on experimentally analyzing shock train/boundary layer interactions from multiple perspectives in aspect ratio 1.0, 3.0, and 6.0 rectangular isolators with inflow Mach numbers ranging from 2.4 to 2.7. Secondary steady-state Computational Fluid Dynamics studies are performed to compare to the experimental results and to provide additional perspectives of the flow field. Specific issues that remain unresolved after decades of isolator shock train studies that are addressed in this work include the three-dimensional formation of the isolator shock train front, the spatial and temporal low momentum corner flow separation scales, the transient behavior of shock train/boundary layer interaction at specific coordinates along the isolator's lateral axis, and effects of the rectangular geometry on semi-empirical relations for shock train length prediction. A novel multiplane shadowgraph technique is developed to resolve the structure of the shock train along both the minor and major duct axis simultaneously. It is shown that the shock train front is of a hybrid oblique/normal nature. Initial low momentum corner flow separation spawns the formation of oblique shock planes which interact and proceed toward the center flow region, becoming more normal in the process. The hybrid structure becomes more two-dimensional as aspect ratio is increased but corner flow separation precedes center flow separation on the order of 1 duct height for all aspect ratios considered. Additional instantaneous oil flow surface visualization shows the symmetry of the three-dimensional shock train front around the lower wall centerline. Quantitative synthetic schlieren visualization shows the density gradient magnitude approximately double between the corner oblique and center flow normal structures. Fast response pressure measurements acquired near the corner region of the duct show preliminary separation in the outer regions preceding centerline separation on the order of 2 seconds. Non-intrusive Focusing Schlieren Deflectometry Velocimeter measurements reveal that both shock train oscillation frequency and velocity component decrease as measurements are taken away from centerline and towards the side-wall region, along with confirming the more two dimensional shock train front approximation for higher aspect ratios. An updated modification to Waltrup \& Billig's original semi-empirical shock train length relation for circular ducts based on centerline pressure measurements is introduced to account for rectangular isolator aspect ratio, upstream corner separation length scale, and major- and minor-axis boundary layer momentum thickness asymmetry. The latter is derived both experimentally and computationally and it is shown that the major-axis (side-wall) boundary layer has lower momentum thickness compared to the minor-axis (nozzle bounded) boundary layer, making it more separable. Furthermore, it is shown that the updated correlation drastically improves shock train length prediction capabilities in higher aspect ratio isolators. This thesis suggests that performance analysis of rectangular confined supersonic flow fields can no longer be based on observations and measurements obtained along a single axis alone. Knowledge gained by the work performed in this study will allow for the development of more robust shock train leading edge detection techniques and isolator designs which can greatly mitigate the risk of inlet unstart and/or vehicle loss in flight.

"Ich sehe was, was Du nicht siehst…“ – Was Rineke Dijkstra mit ihrem Video I see a woman crying (Weeping Woman) vor Augen führt

Die Autorin interpretiert das Video "I see a woman crying (Weeping Woman)" der niederländischen Künstlerin Rinke Dijkstra unter Aspekten des Bildungsprozesses von Kindern. In der sequentiellen Erschließung einzelner Szenen des Videos kann gezeigt werden, wie ein Gespräch von Kindern ein Kunstwerk thematisiert. Damit wird mit künstlerisch-ästhetischen Mitteln das Bildungsproblem inszeniert. (DIPF/Autor)

Carrier frequency effect on the MIMO eigenvalues in an indoor environment

El efecto de la frecuencia portadora sobre los valores propios de los sistemas MIMO (multiple-input multiple-output) es investigado experimentalmente en un entorno indoor, considerando condiciones de línea de vista (LOS: line-of-sight) y sin línea de vista (NLOS: non-line-of-sight). Los resultados muestran una reducción en la potencia media de los valores propios del sistema MIMO, lo cual es debido a un incremento en la correlación espacial entre los sub-canales cuando la frecuencia portadora se incrementa. Este efecto causa una reducción en la capacidad del sistema MIMO.

O contributo de materiais autênticos para o ensino da competência sociocultural nas aulas de espanhol língua estrangeira

O presente Relatório Final visa aferir a importância que os materiais autênticos podem proporcionar ao ensino da competência sociocultural nas aulas de Espanhol Língua Estrangeira (ELE), contrariando a visão da abordagem cultural no ensino de línguas estrangeiras como mais uma tarefa. O objetivo primordial é estreitar laços entre língua e cultura, explorando as potencialidades dos materiais autênticos. Propõe-se, desta forma, a realização de fichas de trabalho apoiadas nestes materiais, com o intuito de motivar os alunos para a aprendizagem da língua espanhola, associando, sempre, idioma, cultura e comunicação, dado que a competência sociocultural compreende conhecimentos que nos permitem utilizar uma Língua Estrangeira (LE) de modo eficaz e adequado, em diferentes atos comunicativos em que o falante possa estar envolvido, por forma a evitar prováveis situações constrangedoras.

The 1998 BFA Graduating Class: Department of Visual Arts

The exhibition of works by Sir Wilfred Grenfell College's graduating Class in visual arts constitutes the culmination of four years of intensive study and practice. our students are trained in the fundamentals of their craft and exposed tio a variety of media and styles ranging from the traditional to the avant garde. But their education has more to do with the exploration and development of their creativity, the enlargement of their capacity to see, and their mastery of the vocabulary of sight, enabling them to discover, uncover and represent. Each of the students ha sustained and nurtured an individual and unique quest over the four years of this rigorous programme.

Extensão universitária e associativismo popular : um estudo a partir da educação ambiental crítica

Partimos do pressuposto que a universidade pública é um bem do povo e deve servir aos interesses da sociedade, sobretudo aos interesses daqueles cuja vida é ameaçada mediante as condições desiguais sob as quais a sociedade capitalista se funda. Entendemos que a extensão universitária é uma atividade da universidade e deve, como ensino e pesquisa, ser reconhecida como produtora de conhecimentos e não por trabalhos assistenciais, como se caracteriza, na realidade concreta, a extensão universitária analisada nesta dissertação. Com base nisso, o trabalho que se segue discorre sobre a relação de dependência das associações populares, ligadas ao movimento da economia popular solidária à extensão da Universidade Federal do Rio Grande – FURG, especificamente aquela realizada pelo Núcleo de Desenvolvimento Social e Econômico – NUDESE-FURG, da região de Rio GrandeRS. O objetivo do trabalho foi conhecer a relação entre o núcleo e as associações, problematizando-a com base em alguns princípios da Educação Ambiental Crítica (diálogo, totalidade, relação teoria/prática e participação social). O referencial que sustenta o trabalho articula autores da sociologia do trabalho, economia da educação, ecologia política, geografia crítica, todos, de alguma forma, ligados ao materialismo histórico como perspectiva de análise. O trabalho se caracteriza como um estudo de caso, onde os principais recursos perpassaram pela análise de documentos e, fundamentalmente, as entrevistas gravadas e transcritas na íntegra, pelas quais nosso estudo se baseia. A análise do material foi feita a partir dos pressupostos da análise crítica do discurso, a qual busca entrelaçar os pronunciamentos dos sujeitos com a totalidade social na qual o discurso está inscrito, possibilitando o alcance do significado concreto. O estudo demonstra que a extensão universitária desenvolvida pelo NUDESE-FURG tem características assistencialistas, cuja consequência prática é a realização de atividades para os trabalhadores associados (principalmente elaboração e gestão de projetos), impedindo que as associações desenvolvam suas ações sem depender do núcleo. Além disso, ao assumir recursos financeiros oriundos de projetos (via editais), as associações apenas transferem para o Estado a condição de dependência do intermediário, o que não extingue o problema, mas reafirma-o. Por isso, entendemos que a Educação Ambiental Crítica oferece, por meio dos princípios que utilizamos, um instrumento crítico importante ao estudo de processos e políticas que buscam a emancipação dos sujeitos. Isso porque, também, ao reconhecer a crise socioambiental que vivemos, fruto do modo de produção capitalista, dos conflitos existentes na sociedade (portanto dos diferentes interesses, concepções e valores em disputa), pela apropriação da riqueza produzida, podem-se possibilitar conhecimentos úteis dos trabalhadores das associações. Para que isso aconteça, defendemos o encontro da extensão universitária do NUDESE-FURG com a Educação Ambiental Crítica, caso a emancipação, de fato, esteja no horizonte das práticas deste núcleo, já que pelo estudo, nesta pesquisa, predomina dependência de tais grupos do NUDESE-FURG.

Em que medida a estimulação cognitiva vertente estimulação sensorial, contribui para o bem estar e qualidade de vida da pessoa idosa com demência

Trabalho de Projeto apresentado à Escola Superior de Educação de Paula Frassinetti para obtenção do grau de mestre em Intervenção Comunitária, especialização em Educação para a Saúde

Investigation of multisensory processing and structural brain differences in Autism Spectrum Disorder

This thesis is an investigation of structural brain abnormalities, as well as multisensory and unisensory processing deficits in autistic traits and Autism Spectrum Disorder (ASD). To achieve this, structural and functional magnetic resonance imaging (fMRI) and psychophysical techniques were employed. ASD is a neurodevelopmental condition which is characterised by the social communication and interaction deficits, as well as repetitive patterns of behaviour, interests and activities. These traits are thought to be present in a typical population. The Autism Spectrum Quotient questionnaire (AQ) was developed to assess the prevalence of autistic traits in the general population. Von dem Hagen et al. (2011) revealed a link between AQ with white matter (WM) and grey matter (GM) volume (using voxel-based-morphometry). However, their findings revealed no difference in GM in areas associated with social cognition. Cortical thickness (CT) measurements are known to be a more direct measure of cortical morphology than GM volume. Therefore, Chapter 2 investigated the relationship between AQ scores and CT in the same sample of participants. This study showed that AQ scores correlated with CT in the left temporo-occipital junction, left posterior cingulate, right precentral gyrus and bilateral precentral sulcus, in a typical population. These areas were previously associated with structural and functional differences in ASD. Thus the findings suggest, to some extent, autistic traits are reflected in brain structure - in the general population. The ability to integrate auditory and visual information is crucial to everyday life, and results are mixed regarding how ASD influences audiovisual integration. To investigate this question, Chapter 3 examined the Temporal Integration Window (TIW), which indicates how precisely sight and sound need to be temporally aligned so that a unitary audiovisual event can be perceived. 26 adult males with ASD and 26 age and IQ-matched typically developed males were presented with flash-beep (BF), point-light drummer, and face-voice (FV) displays with varying degrees of asynchrony and asked to make Synchrony Judgements (SJ) and Temporal Order Judgements (TOJ). Analysis of the data included fitting Gaussian functions as well as using an Independent Channels Model (ICM) to fit the data (Garcia-Perez & Alcala-Quintana, 2012). Gaussian curve fitting for SJs showed that the ASD group had a wider TIW, but for TOJ no group effect was found. The ICM supported these results and model parameters indicated that the wider TIW for SJs in the ASD group was not due to sensory processing at the unisensory level, but rather due to decreased temporal resolution at a decisional level of combining sensory information. Furthermore, when performing TOJ, the ICM revealed a smaller Point of Subjective Simultaneity (PSS; closer to physical synchrony) in the ASD group than in the TD group. Finding that audiovisual temporal processing is different in ASD encouraged us to investigate the neural correlates of multisensory as well as unisensory processing using functional magnetic resonance imaging fMRI. Therefore, Chapter 4 investigated audiovisual, auditory and visual processing in ASD of simple BF displays and complex, social FV displays. During a block design experiment, we measured the BOLD signal when 13 adults with ASD and 13 typically developed (TD) age-sex- and IQ- matched adults were presented with audiovisual, audio and visual information of BF and FV displays. Our analyses revealed that processing of audiovisual as well as unisensory auditory and visual stimulus conditions in both the BF and FV displays was associated with reduced activation in ASD. Audiovisual, auditory and visual conditions of FV stimuli revealed reduced activation in ASD in regions of the frontal cortex, while BF stimuli revealed reduced activation the lingual gyri. The inferior parietal gyrus revealed an interaction between stimulus sensory condition of BF stimuli and group. Conjunction analyses revealed smaller regions of the superior temporal cortex (STC) in ASD to be audiovisual sensitive. Against our predictions, the STC did not reveal any activation differences, per se, between the two groups. However, a superior frontal area was shown to be sensitive to audiovisual face-voice stimuli in the TD group, but not in the ASD group. Overall this study indicated differences in brain activity for audiovisual, auditory and visual processing of social and non-social stimuli in individuals with ASD compared to TD individuals. These results contrast previous behavioural findings, suggesting different audiovisual integration, yet intact auditory and visual processing in ASD. Our behavioural findings revealed audiovisual temporal processing deficits in ASD during SJ tasks, therefore we investigated the neural correlates of SJ in ASD and TD controls. Similar to Chapter 4, we used fMRI in Chapter 5 to investigate audiovisual temporal processing in ASD in the same participants as recruited in Chapter 4. BOLD signals were measured while the ASD and TD participants were asked to make SJ on audiovisual displays of different levels of asynchrony: the participants’ PSS, audio leading visual information (audio first), visual leading audio information (visual first). Whereas no effect of group was found with BF displays, increased putamen activation was observed in ASD participants compared to TD participants when making SJs on FV displays. Investigating SJ on audiovisual displays in the bilateral superior temporal gyrus (STG), an area involved in audiovisual integration (see Chapter 4), we found no group differences or interaction between group and levels of audiovisual asynchrony. The investigation of different levels of asynchrony revealed a complex pattern of results indicating a network of areas more involved in processing PSS than audio first and visual first, as well as areas responding differently to audio first compared to video first. These activation differences between audio first and video first in different brain areas are constant with the view that audio leading and visual leading stimuli are processed differently.

Percepcja walorów turystycznych przez osoby niesłyszące na tle słyszącej części społeczeństwa w Polsce

The article aims at showing similarities and differences in the perception of tourist attractions among tourists with and without hearing impairment. The first part depicts perception problems from the theoretical point of view. Complexities of studies on the perception system have been described. The perception itself is channelled via senses, including mainly sight (reception of approximately 87% of outside factors), hearing (7%), smell (3–5%), touch (1–5%) and taste (1%) (Visual Landscape… 1994, after: Pietrzak 2008). The data suggests that people with hearing impairment, owing to dominative position of sight perception and to other senses (except hearing), should perceive outside factors similarly to people with no hearing impairment, also in terms of tourist attractions. Is this really a fact? The attempt to answer this question resulted in conducting questionnaire study among the tourists, both with and without hearing impairment. The data was collected, based on questionnaire study, conducted nationwide in years 2004–2010 among the 292 deaf (for whom Polish Sign Language is the main method of communication) and 1780 people without hearing impairment. The aim of this study was to reveal, if tourists with hearing dysfunction have different tourist preferences than those without any hearing disabilities and to indicate which tourist attractions are the most significant for tourists with hearing impairment. The percentage values and the level of signi-ficance (p), calculated on the basis of Pearson’s chi-square test (with border value of p ≤ 0.05), were used in the analysis It was determined, that in case of perception of natural tourist attractions, there is a major similarity (both, people with and without hearing impairment indicated such attractions as sea, lake, clean natural environment, natural landscape, climate and diversified land relief, including mountains). As far as cultural attractions are concerned, a similarity in perception of both studied groups can also be observed. The most popular attractions include those, which can be perceived with sight: monuments, historic landmarks, museums, open-air museums, places of worship and modern architecture. The biggest differences are related to culture and entertainment, which indicates a social aspect of the disability of people with hearing impairment (a discomfort of being in environ-ment, where sound is the main carrier of information). The conclusions from the conducted analyses are applicative in their nature. They contain hints for tour operators, involved in creating tourist offer for people using Polish Sign Language, taking into account their preferences, perception abilities and ensuring pleasant tourist experience.

Tradução parcial comentada do estudo Emigrantes Deportados nos Açores

Dissertação de Mestrado, Tradução e Assessoria Linguística, 13 de Junho de 2016, Universidade dos Açores.

El reverso del sujeto: provocaciones de Foucault para pensar en derechos humanos

Este ensayo pretende discutir los modos de subjetivación propuestos por Michel Foucault y los derechos humanos. Tomando esas implicaciones Faucaultianas del cuidado de sí mismo y de una estilización de la existencia de la constitución en nuestras vidas, es posible substituir el llamado a lo universal y lo esencial por formas más disonantes de subjetivación, significativamente más singulares. Este ensayo se enfocó en un referencial bibliográfico que contempla obras de Foucault y obras sobre el autor, sobre derechos humanos, sin perder de vista las implicaciones practicas y las experiencias del campo jurídico. Sin embargo, la percepción de las insuficiencias de la teoría tradicional de los derechos humanos de encarar las diferencias de la subjetividad y de promover la autonomía y la emancipación de los sujetos, evidencia el motivo por el cual buscamos elementos nuevos de la subjetividad en la filosofía de Foucault y en una teoría critica de los derechos humanos..

Investigating the cosmic-ray ionization rate in the galactic interstellar medium through observations of H3+

Observations of H3+ in the Galactic diffuse interstellar medium (ISM) have led to various surprising results, including the conclusion that the cosmic-ray ionization rate (zeta_2) is about 1 order of magnitude larger than previously thought. The present survey expands the sample of diffuse cloud sight lines with H3+ observations to 50, with detections in 21 of those. Ionization rates inferred from these detections are in the range (1.7+-1.0)x10^-16 s^-1 < zeta_2 < (10.6+-6.8)x10^-16 s^-1 with a mean value of zeta_2=(3.3+-0.4)x10^-16 s^-1. Upper limits (3sigma) derived from non-detections of H3+ are as low as zeta_2 < 0.4x10^-16 s^-1. These low upper-limits, in combination with the wide range of inferred cosmic-ray ionization rates, indicate variations in zeta_2 between different diffuse cloud sight lines. Calculations of the cosmic-ray ionization rate from theoretical cosmic-ray spectra require a large flux of low-energy (MeV) particles to reproduce values inferred from observations. Given the relatively short range of low-energy cosmic rays --- those most efficient at ionization --- the proximity of a cloud to a site of particle acceleration may set its ionization rate. Variations in zeta_2 are thus likely due to variations in the cosmic-ray spectrum at low energies resulting from the effects of particle propagation. To test this theory, H3+ was observed in sight lines passing through diffuse molecular clouds known to be interacting with the supernova remnant IC 443, a probable site of particle acceleration. Where H3+ is detected, ionization rates of zeta_2=(20+-10)x10^-16 s^-1 are inferred, higher than for any other diffuse cloud. These results support both the concept that supernova remnants act as particle accelerators, and the hypothesis that propagation effects are responsible for causing spatial variations in the cosmic-ray spectrum and ionization rate. Future observations of H3+ near other supernova remnants and in sight lines where complementary ionization tracers (OH+, H2O+, H3O+) have been observed will further our understanding of the subject.

A contribution to semantic description of images and videos: an application of soft biometrics

Humans have a high ability to extract visual data information acquired by sight. Trought a learning process, which starts at birth and continues throughout life, image interpretation becomes almost instinctively. At a glance, one can easily describe a scene with reasonable precision, naming its main components. Usually, this is done by extracting low-level features such as edges, shapes and textures, and associanting them to high level meanings. In this way, a semantic description of the scene is done. An example of this, is the human capacity to recognize and describe other people physical and behavioral characteristics, or biometrics. Soft-biometrics also represents inherent characteristics of human body and behaviour, but do not allow unique person identification. Computer vision area aims to develop methods capable of performing visual interpretation with performance similar to humans. This thesis aims to propose computer vison methods which allows high level information extraction from images in the form of soft biometrics. This problem is approached in two ways, unsupervised and supervised learning methods. The first seeks to group images via an automatic feature extraction learning , using both convolution techniques, evolutionary computing and clustering. In this approach employed images contains faces and people. Second approach employs convolutional neural networks, which have the ability to operate on raw images, learning both feature extraction and classification processes. Here, images are classified according to gender and clothes, divided into upper and lower parts of human body. First approach, when tested with different image datasets obtained an accuracy of approximately 80% for faces and non-faces and 70% for people and non-person. The second tested using images and videos, obtained an accuracy of about 70% for gender, 80% to the upper clothes and 90% to lower clothes. The results of these case studies, show that proposed methods are promising, allowing the realization of automatic high level information image annotation. This opens possibilities for development of applications in diverse areas such as content-based image and video search and automatica video survaillance, reducing human effort in the task of manual annotation and monitoring.

Bioleta Mata: una planta que interactúa por medio de realidad aumentada

Este documento describe una planta real dotada de un vehículo inteligente que le permite navegar por ambientes de interiores, responder a estímulos del ambiente, interactuar con seres humanos a través de realidad aumentada, detectar la presencia de fuego y solicitar ayuda por medio de Twitter. Los experimentos muestran que no hay falsos positivos en la detección de fuego, y que la detección de fuego es superior al 50% de las lecturas del sensor en distancias menores a 5 m, con línea de visión entre el sensor y la llama. La comunicación por radios XBee en ambientes de interiores es efectiva hasta por lo menos 25m de distancia entre los radios.

A formação e o desenvolvimento de arranjos cooperativos sob a ótica da imersão social e da economia dos custos de transação: um estrudo de caso na Coopercam e na Unipesca

The current study analyzes the birth and development of two strategic alliances established between shrimp producers in Rio Grande do Norte: the Unipesca and the Coopercam. To achieve this aim, two approaches which, at first sight, could be considered contradictory were used: the Transactional Costs Economy and Embeddedness. The first approach is fundamentally based in the studies of Williamson (1985; 1991; 1996; 1999; 2000; 2002). Embededness, on the other hand, went through the review of a series of authors, such as Burt (1992), Granovetter (1973; 1985), Uzzi (1997), Gulati (1994; 1995; 1997; 1998; 1999; 2000), Nielsen (2005), Ring (2002), Ring and Van de Ven (1994), Zafirovski (2002), among others. To analyze the birth and development of the cooperatives in this study, Gulati s work (1998) was used. This study shows the steps to be studied for a better comprehension of an alliance: the decision of starting an alliance and the choice of the partners, the decision about the governance structure, the evolution of the alliance and the development of the companies which established this partnership. To carry this study out, a study case accordingly to Yin s proposal (2001) was adopted. Semi-structured interviews with pre-defined plots were conducted in two phases: in the beginning of 2006 and in the beginning of 2007. The subjects from the research were, in 2006, representative members of the main associations and corporations, besides the shrimp producers from the state, when the context of the activity was set. In the second phase, in 2007, representative members from the two cooperatives that were listed above were interviewed the president from Coopercam and the marketing manager from Unipesca. Besides these two members, directors from two important organizations in each of these cooperatives were also interviewed, giving out the necessary information for the research. Secondary data was also collected from the Brazilian Association of Crab producers website, as well as from news from important newspapers in RN, such as Tribuna do Norte. The primary data was analyzed in terms of quality, accordingly to the documental analysis technique. Thus, through the data that was collected, it can be concluded that the reasons that motivated the companies to cooperate can be explained in terms of the transactional costs economy. However, the choice of partners is more connected to aspects approached by the social embededness. When aspects related to development and evolution were analyzed, it could be seen that both aspects from TCE and Embededness were vital to explain the development of the cooperatives mentioned