834 resultados para Collapsed objects and Supernovae
Resumo:
The Unified Modeling Language (UML) has quickly become the industry standard for object-oriented software development. It is being widely used in organizations and institutions around the world. However, UML is often found to be too complex for novice systems analysts. Although prior research has identified difficulties novice analysts encounter in learning UML, no viable solution has been proposed to address these difficulties. Sequence-diagram modeling, in particular, has largely been overlooked. The sequence diagram models the behavioral aspects of an object-oriented software system in terms of interactions among its building blocks, i.e. objects and classes. It is one of the most commonly-used UML diagrams in practice. However, there has been little research on sequence-diagram modeling. The current literature scarcely provides effective guidelines for developing a sequence diagram. Such guidelines will be greatly beneficial to novice analysts who, unlike experienced systems analysts, do not possess relevant prior experience to easily learn how to develop a sequence diagram. There is the need for an effective sequence-diagram modeling technique for novices. This dissertation reports a research study that identified novice difficulties in modeling a sequence diagram and proposed a technique called CHOP (CHunking, Ordering, Patterning), which was designed to reduce the cognitive load by addressing the cognitive complexity of sequence-diagram modeling. The CHOP technique was evaluated in a controlled experiment against a technique recommended in a well-known textbook, which was found to be representative of approaches provided in many textbooks as well as practitioner literatures. The results indicated that novice analysts were able to perform better using the CHOP technique. This outcome seems have been enabled by pattern-based heuristics provided by the technique. Meanwhile, novice analysts rated the CHOP technique more useful although not significantly easier to use than the control technique. The study established that the CHOP technique is an effective sequence-diagram modeling technique for novice analysts.
Resumo:
SmartWater is a chemical taggant used as a crime deterrent. The chemical taggant is a colorless liquid that fluoresces yellow under ultra-violet (UV) light and contains distinctive, identifiable and traceable elemental composition. For instance, upon a break and entry scenario, the burglar is sprayed with a solution that has an elemental signature custom-made to a specific location. The residues of this taggant persist on skin and other objects and can be easily recovered for further analysis. The product has been effectively used in Europe as a crime deterrent and has been recently introduced in South Florida. In 2014, Fourt Lauderdale Police Department reported the use of SmartWater products with a reduction in burglaries of 14% [1]. The International Forensic Research Institute (IFRI) at FIU validated the scientific foundation of the methods of recovery and analysis of these chemical tagging systems using LA-ICP-MS. Analytical figures of merit of the method such as precision, accuracy, limits of detection, linearity and selectivity are reported in this study. Moreover, blind samples were analyzed by LA-ICP-MS to compare the chemical signatures to the company’s database and evaluate error rates and the accuracy of the method. This study demonstrated that LA-ICP-MS could be used to effectively detect these traceable taggants to assist law enforcement agencies in the United States with cases involving transfer of these forensic coding systems.
Resumo:
This research aims to systematize a proposal of developing a mobile tablet application in order to help implementing the Semantic Differential technique – SD, under the approach of Participatory Design. In 1975, Osgood et al. created the Semantic Differential technique. Since then, many experiments use it to measure the affective perception of individuals concerning objects and concepts by means of compounded scales of bipolar adjectives, based on the theoretical models that support the technique: the conductible, spatial and metric models. During the application of the technique with potential users, the researcher must simultaneously manage several contexts, that is, audio recorder, when authorized, and observe and record spontaneous reports of the respondent. It is noticeable that often occurs a cognitive overload during this event. Thus, the use of a single application whose interface is assigned to its users and respondents could assist researchers in applying the SD technique. This research aimed to understand the processes inherent to the task of implementing the Semantic Differential technique and obeyed the following steps: a) training of users, b) background questionnaire c) interview with Focus Group, and d) cooperative evaluation. Besides these procedures, one can also observe the degrees of facilitation or difficulty concerning the use of the conventional model, which is the development and application of scales with the aid of printed material, pencil, pens, clipboards, and recorder software for editing the document and data analysis. This paper comprises reactions and impressions from the experiences of users of SD technique. Considering the data recollected from the user’s observation, the hypothesis of the experiment proved to be right. It means that the development of the application for mobile tablet employing the technique of Semantic Differential is viable, since it assembles all the steps in one only tool, increases the accomplishment of the task between user/researcher and user/respondent resulting in their mutual satisfaction.
Resumo:
This study aims to understand the growth dynamics of Ceará-Mirim city considering the aspects that define its current urban sprawl. We chose to use as methodological approach the concept of space as a product and producer of social relations and the same constitutes by objects and actions that relate in a dialectical process over time. As a research tool, it took place bibliographical study that features the historical aspects of use and occupation, in order to evidence the regional ground agents that explain its current urban setting. Then, it was collected a secondary data of economic analysis activities from municipality and their impact on local social structure. Between these aspects, the sugar economy, even in decline, had appeared as defining the boundaries of urban growth. At the regional scale, other factors were discussed in a way of urban influence processes forming the Greater Natal (RMNatal), and Ceará-Mirim appears integrating into this scale in a very low level according to Metropolis Observatory (2012). However, we have pointed out that in recent years, especially in growth vector of BR 406, settled metropolitan scope equipment. These objects have been associating in a real estate sector's reasoning while the possible "metropolization" have been promoting as investments in the city's expansion area.
Resumo:
This study suggests sonorous ambiences from the propose of images configured according to the description in “A Visagem da Moça Caetana” by Ariano Suassuna in order to create individual sonorous possibilities that may help musicians to play the piece. The cycle, composed in 1996 (for voice, viola, cello, bass clarinet/clarinet), is formed by three untitled songs. Its text is an excerpt from the “Folheto XLIV”, from the Romance d’A Pedra do Reino e o príncipe do sangue do vai-e-volta, and describes a sentence of death illustrated by symbols of the Armorial imagery, with neologisms and the peculiar accent from the Sertão in northeast Brazil. In addition to the analysis of technical difficulties to play, this study informs interpreters of the sonorous timbre and texture used by Nelson Almeida to describe tradition through contemporary musical language. The metaphors and transgressions of reason in Suassuna’s book were explored to create three image compositions so that they may lead interpreters to the sonorous description of the inanimate objects and the affections to which the poetry refers, expanding any technical-interpretative indications limited by musical notation. This research used the Visagem scores, the literature on the theme, discussions with the musicians that played the piece, interviews with Almeida, and composers’ reports. To illustrate the theory, the three images are available, printed as woodcut in cordel literature.
Resumo:
A certain type of bacterial inclusion, known as a bacterial microcompartment, was recently identified and imaged through cryo-electron tomography. A reconstructed 3D object from single-axis limited angle tilt-series cryo-electron tomography contains missing regions and this problem is known as the missing wedge problem. Due to missing regions on the reconstructed images, analyzing their 3D structures is a challenging problem. The existing methods overcome this problem by aligning and averaging several similar shaped objects. These schemes work well if the objects are symmetric and several objects with almost similar shapes and sizes are available. Since the bacterial inclusions studied here are not symmetric, are deformed, and show a wide range of shapes and sizes, the existing approaches are not appropriate. This research develops new statistical methods for analyzing geometric properties, such as volume, symmetry, aspect ratio, polyhedral structures etc., of these bacterial inclusions in presence of missing data. These methods work with deformed and non-symmetric varied shaped objects and do not necessitate multiple objects for handling the missing wedge problem. The developed methods and contributions include: (a) an improved method for manual image segmentation, (b) a new approach to 'complete' the segmented and reconstructed incomplete 3D images, (c) a polyhedral structural distance model to predict the polyhedral shapes of these microstructures, (d) a new shape descriptor for polyhedral shapes, named as polyhedron profile statistic, and (e) the Bayes classifier, linear discriminant analysis and support vector machine based classifiers for supervised incomplete polyhedral shape classification. Finally, the predicted 3D shapes for these bacterial microstructures belong to the Johnson solids family, and these shapes along with their other geometric properties are important for better understanding of their chemical and biological characteristics.
Resumo:
Loss of limb results in loss of function and a partial loss of freedom. A powered prosthetic device can partially assist an individual with everyday tasks and therefore return some level of independence. Powered upper limb prostheses are often controlled by the user generating surface electromyographic (SEMG) signals. The goal of this thesis is to develop a virtual environment in which a user can control a virtual hand to safely grasp representations of everyday objects using EMG signals from his/her forearm muscles, and experience visual and vibrotactile feedback relevant to the grasping force in the process. This can then be used to train potential wearers of real EMG controlled prostheses, with or without vibrotactile feedback. To test this system an experiment was designed and executed involving ten subjects, twelve objects, and three feedback conditions. The tested feedback conditions were visual, vibrotactile, and both visual and vibrotactile. In each experimental exercise the subject attempted to grasp a virtual object on the screen using the virtual hand controlled by EMG electrodes placed on his/her forearm. Two metrics were used: score, and time to task completion, where score measured grasp dexterity. It was hypothesized that with the introduction of vibrotactile feedback, dexterity, and therefore score, would improve and time to task completion would decrease. Results showed that time to task completion increased, and score did not improve with vibrotactile feedback. Details on the developed system, the experiment, and the results are presented in this thesis.
Resumo:
La organización del conocimiento en el contexto de las Ciencias de la Información tiene como esencia la información y el conocimiento debidamente documentado o registrado. La organización del conocimiento como proceso, envuelve tanto la descripción física como de los contenidos de los objetos informacionales. Y el producto de ese proceso descriptivo es la representación de los atributos de un objeto o conjunto de objetos. Las representaciones son construidas por lenguajes elaborados específicamente para los objetivos de la organización en los sistemas de información. Lenguajes que se subdividen en lenguajes que describen el documento (el soporte físico del objeto) y lenguajes que describen la información (los contenidos).A partir de esta premisa la siguiente investigación tiene como objetivo general analizarlos sistemas de Gestión de Información y Conocimiento Institucional principalmente los que proponen utilizar el Currículum Vitae del profesor como única fuente de información, medición y representación de la información y el conocimiento de una organización. Dentro delos principales resultados se muestra la importancia de usar el currículo personal como fuente de información confiable y normalizada; una síntesis de los principales sistemas curriculares que existen a nivel internacional y regional; así como el gráfico del modelo de datos del caso de estudio; y por último, la propuesta del uso de las ontologías como principal herramienta para la organización semántica de la información en un sistema de gestión de información y conocimiento.
Resumo:
Nowadays, archaeology is trying to redefine its relation with objects. This change is taking place at the same time as the West is breaking once and for all with the generation who did the rural exodus in the mid of the twentieth century. The present paper proposes a revision of the conditions that allow us to both define this rupture and at the same time determine our affinity with materiality. This is done through a reconsideration of the relation between the past and the present and the dynamics marking this difference. We are situated in a moment when the experience of time is shifting and thus so is the integrity of archaeological objects. Under the name of Negative Archaeology, the border between past and present is explored. This border determines the creation of the past in a present which intends to homogenise changes. Archaeology is a unique discipline which could prevent this process, or at least bear witness to the dynamics to which objects seem to be subjected. Obscolescence is introduced as a concept in an attempt to name the aforementioned problem.
Resumo:
Durante las tres últimas décadas, numerosos/as arqueólogos/as han discutido extensamente sobre el ritual funerario original de las poblaciones del sur ibérico entre los siglos ix y vi a.c., esto es, cremación o inhumación. Este debate está además conectado con la existencia o no de complejidad social antes de la llegada fenicia, con la aparición de una élite “orientalizada” y con la adopción de nuevos objetos y prácticas por las poblaciones locales. En este artículo hago uso del concepto deleuziano de “desterritorialización” y lo asocio con el de “frontera” desarrollado por anzaldúa para interpretar la sociedad del sur ibérico. Para ello, analizo la evidencia funeraria indígena y cuestiono la división estricta entre cremación e inhumación en la región; así como examino la profundidad y significado de los cambios funerarios en las comunidades locales.
Resumo:
Las mecánicas patrimoniales se han basado tradicionalmente en factores racionales, marginando aquellos de carácter más emotivo o relacional. Además, en los últimos tiempos el sesgo economicista las ha obligado a buscar la rentabilidad y participar en el juego de la oferta y la demanda, con unos resultados muy poco esperanzadores. Cambiar ese estado de cosas pasa por cambiar radicalmente las estrategias puestas en marcha, basarse en la interlocución, conocer las relaciones entre el patrimonio y los colectivos sociales y, sobre todo, cambiar nuestra manera de pensar en el patrimonio.
Resumo:
The category of rational SO(2)--equivariant spectra admits an algebraic model. That is, there is an abelian category A(SO(2)) whose derived category is equivalent to the homotopy category of rational$SO(2)--equivariant spectra. An important question is: does this algebraic model capture the smash product of spectra? The category A(SO(2)) is known as Greenlees' standard model, it is an abelian category that has no projective objects and is constructed from modules over a non--Noetherian ring. As a consequence, the standard techniques for constructing a monoidal model structure cannot be applied. In this paper a monoidal model structure on A(SO(2)) is constructed and the derived tensor product on the homotopy category is shown to be compatible with the smash product of spectra. The method used is related to techniques developed by the author in earlier joint work with Roitzheim. That work constructed a monoidal model structure on Franke's exotic model for the K_(p)--local stable homotopy category. A monoidal Quillen equivalence to a simpler monoidal model category that has explicit generating sets is also given. Having monoidal model structures on the two categories removes a serious obstruction to constructing a series of monoidal Quillen equivalences between the algebraic model and rational SO(2)--equivariant spectra.
Resumo:
In the past two decades we have witnessed a series of epistemological shifts, springing from traditional area studies and departing from nationally bounded fields. These moves seem to dislocate and problematize categories of identity by focusing on translocality and by calling attention to processes of displacement, dispersion, objects and ideas, and to the new cultural and imaginary territories that these mobilizations effect. Such formulations, while historically situated, illuminate flows and favour transformation, as opposed to producing ontological crystallisations. This issue will explore the view that the creation of new cultural phenomena may be achieved, in the richest of ways, through the mixing of genres and the crossing of media. It will seek to investigate how various contemporary art forms serve to express, envision, challenge and renegotiate Francophone identities that reach across cultures.
Resumo:
Collisionless shocks, that is shocks mediated by electromagnetic processes, are customary in space physics and in astrophysics. They are to be found in a great variety of objects and environments: magnetospheric and heliospheric shocks, supernova remnants, pulsar winds and their nebulæ, active galactic nuclei, gamma-ray bursts and clusters of galaxies shock waves. Collisionless shock microphysics enters at different stages of shock formation, shock dynamics and particle energization and/or acceleration. It turns out that the shock phenomenon is a multi-scale non-linear problem in time and space. It is complexified by the impact due to high-energy cosmic rays in astrophysical environments. This review adresses the physics of shock formation, shock dynamics and particle acceleration based on a close examination of available multi-wavelength or in situ observations, analytical and numerical developments. A particular emphasis is made on the different instabilities triggered during the shock formation and in association with particle acceleration processes with regards to the properties of the background upstream medium. It appears that among the most important parameters the background magnetic field through the magnetization and its obliquity is the dominant one. The shock velocity that can reach relativistic speeds has also a strong impact over the development of the micro-instabilities and the fate of particle acceleration. Recent developments of laboratory shock experiments has started to bring some new insights in the physics of space plasma and astrophysical shock waves. A special section is dedicated to new laser plasma experiments probing shock physics.
Resumo:
Abstract Ordnance Survey, our national mapping organisation, collects vast amounts of high-resolution aerial imagery covering the entirety of the country. Currently, photogrammetrists and surveyors use this to manually capture real-world objects and characteristics for a relatively small number of features. Arguably, the vast archive of imagery that we have obtained portraying the whole of Great Britain is highly underutilised and could be ‘mined’ for much more information. Over the last year the ImageLearn project has investigated the potential of "representation learning" to automatically extract relevant features from aerial imagery. Representation learning is a form of data-mining in which the feature-extractors are learned using machine-learning techniques, rather than being manually defined. At the beginning of the project we conjectured that representations learned could help with processes such as object detection and identification, change detection and social landscape regionalisation of Britain. This seminar will give an overview of the project and highlight some of our research results.