Reflexión y refracción de la luz en medios anisótropos

En este proyecto se pretende estudiar el comportamiento de la luz al atravesar medios de diversos materiales, tanto isótropos como anisótropos uniáxicos. Para ello se requiere realizar un estudio previo de las condiciones de contorno aplicables a las ecuaciones de Maxwell en la interfase de dos medios que pueden ser isótropos o anisótropos. En el caso de dos materiales isótropos, la solución del problema son los conocidos coeficientes de Fresnel de reflexión y transmisión. En este trabajo se pretende generalizar el estudio al caso del paso de la luz desde un medio isótropo a otro anisótropo uniáxico (con su eje óptico en orientación arbitraria) y viceversa y al caso de dos materiales anisótropos uniáxicos con ejes ópticos en orientaciones arbitrarias. Es de especial interés el caso de un mismo material uniáxico en el que las dos partes tienen el eje óptico con distinta orientación. Una vez planteadas las condiciones de contorno específicas en cada caso, se obtendrá un conjunto de ecuaciones algebraicas cuya resolución permitirá obtener los coeficientes de reflexión y transmisión buscados. Para plantear el sistema de ecuaciones adecuado, será necesario tener una descripción de las características ópticas de los materiales empleados, la orientación de los ejes ópticos en cada caso, y los posibles ángulos de incidencia. Se realizará un tratamiento matricial de modo que el paquete MatLab permite su inversión de manera inmediata. Se desarrollará una interfaz sencilla, realizada con MatLab, que permita al usuario introducir sin dificultad los datos correspondientes a los materiales de los medios incidente y transmitido, la orientación en espacial del o de los ejes ópticos, de la longitud de onda de trabajo y del ángulo de incidencia del haz de luz, con los que la aplicación realizará los cálculos. Los coeficientes de reflexión y refracción obtenidos serán representados gráficamente en función del ángulo de incidencia. Así mismo se representarán los ángulos transmitidos y reflejados en función del de incidencia. Todo ello de esta forma, que resulte sencilla la interpretación de los datos por parte del usuario. ABSTRACT. The reason for this project is to study the behavior of light when light crosses different media of different materials, isotropic materials and uniaxial anisotropic materials. For this, a previous study is necessary where the boundary conditions apply to Maxwell equations at the interface between two media which can be isotropic and anisotropic. If both materials are isotropic, the Fresnel ccoefficients of reflection and refraction are used to solve the problem. The aim of this work is to generalize a study when light crosses from an isotropic media to a uniaxial anisotropic media, where its axis have arbitrary directions, and vicecersa. The system consisting of two materials with axis in arbitrary directions are also being studied. Once the specific boundary conditions are known in each case, a set of algebraic equations are obtained whose solution allows obtaining the reflection coefficients and refraction coefficients. It is necessary to have a description of the optical characteristics of the materials used; of the directions axis in each case and the possible angle of incidence. A matrix is proposed for later treatment in Matlab that allows the immediate inversion. A simple interface will de developed, manufactured with Matlab, that allows the user to enter data easily corresponding to the incident media and transmission media of the different materials, the special axis directions, the wavelength and the angle of incidence of the light beam. This data is used by the application to perform the necessary calculations to solve the problem. When reflection coefficients and refraction coefficients are obtained, the application draws the graphics in function of the angle of incidence. Also transmitted and reflected angles depending on the incidence are represented. This is to perform a data representation which is a simple interpretation of the user data.

ALFRED: an allele frequency database for diverse populations and DNA polymorphisms—an update

ALFRED (the ALelle FREquency Database) is designed to store and disseminate frequencies of alleles at human polymorphic sites for multiple populations, primarily for the population genetics and molecular anthropology communities. Currently ALFRED has information on over 180 polymorphic sites for more than 70 populations. Since our initial release of the database we have focussed on increasing the quantity and quality of data, making reciprocal links between ALFRED and other related databases, and providing useful tools to make the data more comprehensible to the end user. ALFRED is accessible from the Kidd Lab home page (http://info.med.yale.edu/genetics/kkidd/) or from ALFRED directly (http://alfred.med.yale.edu/alfred/index.asp).

The rise and fall of the medical mediated searcher

The relationship between the development of mediated online literature searching and the recruitment of medical librarians to fill positions as online searchers was investigated. The history of database searching by medical librarians was outlined and a content analysis of thirty-five years of job advertisements in MLA News from 1961 through 1996 was summarized. Advertisements for online searchers were examined to test the hypothesis that the growth of mediated online searching was reflected in the recruitment of librarians to fill positions as mediated online searchers in medical libraries. The advent of end-user searching was also traced to determine how this trend affected the demand for mediated online searching and job availability of online searchers. Job advertisements were analyzed to determine what skills were in demand as end-user searching replaced mediated online searching as the norm in medical libraries. Finally, the trend away from mediated online searching to support of other library services was placed in the context of new roles for medical librarians.

Desempenho propulsivo de embarcações de pesca: estudo aplicado à melhoria das embarcações do Espírito Santo.

Este trabalho apresenta um procedimento simples e robusto para avaliação e análise do desempenho de instalações propulsoras de embarcações de pesca operando no Estado do Espírito Santo. O objetivo é verificar se as embarcações estão operando com baixa eficiência propulsiva, portanto, com consumo de combustível maior do que o desejável, e identificar possíveis ações de melhoria desta eficiência que poderiam ser implementadas com baixo custo. Tendo em vista as condições artesanais da construção e operação das embarcações de pesca no Espírito Santo, o procedimento foi desenvolvido de forma a poder ser aplicado com relativa facilidade pelas pessoas envolvidas na atividade pesqueira artesanal neste Estado. O procedimento envolve o levantamento de informações sobre a geometria do casco, as características da instalação propulsora existente e sobre alguns aspectos do desempenho das embarcações. Para este levantamento são propostos métodos e técnicas suficientemente simples para que possam ser facilmente aplicadas nos estaleiros. Com base nestes dados levantados implementou-se no procedimento proposto diversos algoritmos que permitem determinar o coeficiente propulsivo das embarcações de pesca e a perda de energia útil que ocorre tanto no motor, por conta de condições inadequadas de operação, quanto na transmissão desta energia para o hélice. Para a validação dos métodos e técnicas envolvidos neste procedimento e dos resultados fornecidos por ele, o mesmo foi aplicado em alguns cascos de embarcações de pesca disponíveis em estaleiros visitados no Estado. Para uma destas embarcações o procedimento foi aplicado em sua totalidade, permitindo identificar a baixa eficiência da instalação propulsora e algumas das possíveis causas que provocam a perda de energia útil no sistema. Finalmente, com base nesse exemplo de aplicação, um estudo de possíveis melhorias na instalação propulsora é apresentado ao final do trabalho.

Radar interferometry techniques for the study of ground subsidence phenomena: a review of practical issues through cases in Spain

Subsidence related to multiple natural and human-induced processes affects an increasing number of areas worldwide. Although this phenomenon may involve surface deformation with 3D displacement components, negative vertical movement, either progressive or episodic, tends to dominate. Over the last decades, differential SAR interferometry (DInSAR) has become a very useful remote sensing tool for accurately measuring the spatial and temporal evolution of surface displacements over broad areas. This work discusses the main advantages and limitations of addressing active subsidence phenomena by means of DInSAR techniques from an end-user point of view. Special attention is paid to the spatial and temporal resolution, the precision of the measurements, and the usefulness of the data. The presented analysis is focused on DInSAR results exploitation of various ground subsidence phenomena (groundwater withdrawal, soil compaction, mining subsidence, evaporite dissolution subsidence, and volcanic deformation) with different displacement patterns in a selection of subsidence areas in Spain. Finally, a cost comparative study is performed for the different techniques applied.

A Copernican Turn for Banking Union. CEPS Policy Brief No. 290, 14 May 2013

Despite apparent consensus that the creation of a ‘Banking Union’ is essential for the survival of the euro, progress is painfully slow. The Single Supervisory Mechanism may not be ready before the middle of next year, the Single Resolution Mechanism may require a laborious change of the EU Treaty and common deposit insurance has been postponed into the indefinite future. Any real progress has been prevented by the protracted fights over which government will be the payer of last resort when banks fail because of past bad loans. In this Policy Brief, Thomas Mayer suggests that a radically new approach is needed if there is any prospect of moving beyond this impasse to reach full Banking Union. Instead of trying to move from common bank supervision over to resolution and then on to deposit insurance, he argues that policy-makers should go backwards and start with deposit insurance, move from there to resolution, and end with supervision.

Regional government and the "New Europe"

Introduction. Regional government in contemporary western Europe corresponds to a type of society and economy variously labeled "post-industrial", "post-bourgeois" or merely "the New Europe."l This New Europe evolved historically from the interconnected strands of capitalism; industrialism and pluralistic democracy. It resembles in many respects the type of economy and society familiar to us in North America. Regional government in such a society is thus merely an adaptation on the scale of half a continent of forms of social and economic organization which evolved historically at the national level. Regional government in the New Europe is the institutional and political recognition that societies have changed dramatically since 1945, so dramatically that they cannot be adequately described in the doctrines and ideologies made familiar by nineteenth and early twentieth century political thought. Hence the New Europe and its regional government is the future of that part of history which has also been aptly described as "the end of ideology."

Net Neutrality and Mandatory Network-Sharing: How to disconnect the continent. CEPS Policy Brief No. 309, 18 December 2013

A lively debate emerged on the proposed “Connected Continent” legislative package presented by the European Commission in September 2013. The package contains a proposed rule on the ‘open Internet’, which was heavily discussed in European Parliament hearings in early December. This commentary argues that while the proposed rule is in principle balanced and appealing, it is utterly impractical due to the enormous uncertainty that its application would entail. At the same time, the rule is very far from what neutrality proponents have argued for almost a decade: rather than the place for internet freedom, it would transform the Web into a place requiring constant micro-management and tutoring of user behaviour. Both arguments lead to the conclusion that the current proposal should be at once reformed and analysed under a more holistic lens. On the one hand, Europe should launch an ambitious project for the future, converged infrastructure by mobilising resources and reforming rules to encourage investment into ubiquitous, converged, ‘always on’ connectivity. On the other hand, enhanced legal certainty for broadband investment could justify a more neutrality-oriented approach to traffic management practices on the Internet. The author proposes a new approach to Internet regulation which, altogether, will lead to a more balanced and sustainable model for the future, without jeopardising user freedom.

The impact of depression on patient outcomes among older adults with lung cancer

Thesis (Ph.D.)--University of Washington, 2016-06

Dynamic multi-resolution spatial object derivation for mobile and WWW applications

Online geographic information systems provide the means to extract a subset of desired spatial information from a larger remote repository. Data retrieved representing real-world geographic phenomena are then manipulated to suit the specific needs of an end-user. Often this extraction requires the derivation of representations of objects specific to a particular resolution or scale from a single original stored version. Currently standard spatial data handling techniques cannot support the multi-resolution representation of such features in a database. In this paper a methodology to store and retrieve versions of spatial objects at, different resolutions with respect to scale using standard database primitives and SQL is presented. The technique involves heavy fragmentation of spatial features that allows dynamic simplification into scale-specific object representations customised to the display resolution of the end-user's device. Experimental results comparing the new approach to traditional R-Tree indexing and external object simplification reveal the former performs notably better for mobile and WWW applications where client-side resources are limited and retrieved data loads are kept relatively small.

Selecting optimal instantiations of data models - Theory and validation of an ex ante approach

The schema of an information system can significantly impact the ability of end users to efficiently and effectively retrieve the information they need. Obtaining quickly the appropriate data increases the likelihood that an organization will make good decisions and respond adeptly to challenges. This research presents and validates a methodology for evaluating, ex ante, the relative desirability of alternative instantiations of a model of data. In contrast to prior research, each instantiation is based on a different formal theory. This research theorizes that the instantiation that yields the lowest weighted average query complexity for a representative sample of information requests is the most desirable instantiation for end-user queries. The theory was validated by an experiment that compared end-user performance using an instantiation of a data structure based on the relational model of data with performance using the corresponding instantiation of the data structure based on the object-relational model of data. Complexity was measured using three different Halstead metrics: program length, difficulty, and effort. For a representative sample of queries, the average complexity using each instantiation was calculated. As theorized, end users querying the instantiation with the lower average complexity made fewer semantic errors, i.e., were more effective at composing queries. (c) 2005 Elsevier B.V. All rights reserved.

Toward a business-to-business channel incentives classification scheme

A recent focus on intermediary compensation underscores the need to organize the many complex incentives used by channel practitioners. Employing a grounded theory methodology, a channel incentives classification scheme is induced from 170 unique channel incentives used in 59 high technology suppliers’ channel programs. The incentives are organized into 16 subcategories and 5 major categories: Credible Channel Policies, Market Development Support, Supplemental Contact, High-Powered Incentives, and End-User Encouragements. Each incentive subcategory is discussed as a means of controlling reseller behaviors. Also, the conditions that give rise to the implementation of incentives are investigated through four testable research propositions.

Inter-organizational co-operation, conflict and change

Relationships between organizations can be characterized by cooperation, conflict, and change. In this dissertation we study cooperation between organizations by investigating how norms in relationships can enhance innovativeness and subsequently impact relationship performance. We do so by incorporating both beneficial aspects of long term relationships as well as “dark side” factors that may decrease innovativeness. This provides a balanced assessment of the factors increasing and decreasing the performance of relationships. Next, we study conflict between organizations by taking a network view on conflict which helps explain why organizations react to conflict. We find stakeholders to have an effect on channel conflict responsiveness. Finally we study change by means of an organization’s ability to successfully add an Internet channel to their distribution system in order to sell its products or services directly to the end-user. We find that an Internet channel is best implemented by organizations that are flexible and we identify several circumstances under which this flexibility is highest.

Integrating security services into computer supported cooperative work

This research describes the development of a groupware system which adds security services to a Computer Supported Cooperative Work system operating over the Internet. The security services use cryptographic techniques to provide a secure access control service and an information protection service. These security services are implemented as a protection layer for the groupware system. These layers are called External Security Layer (ESL) and Internal Security Layer (ISL) respectively. The security services are sufficiently flexible to allow the groupware system to operate in both synchronous and asynchronous modes. The groupware system developed - known as Secure Software Inspection Groupware (SecureSIG) - provides security for a distributed group performing software inspection. SecureSIG extends previous work on developing flexible software inspection groupware (FlexSIG) Sahibuddin, 1999). The SecureSIG model extends the FlexSIG model, and the prototype system was added to the FlexSIG prototype. The prototype was built by integrating existing software, communication and cryptography tools and technology. Java Cryptography Extension (JCE) and Internet technology were used to build the prototype. To test the suitability and transparency of the system, an evaluation was conducted. A questionnaire was used to assess user acceptability.

Social and organizational impacts of emerging mobile devices:evaluating use

As mobile devices become increasingly diverse and continue to shrink in size and weight, their portability is enhanced but, unfortunately, their usability tends to suffer. Ultimately, the usability of mobile technologies determines their future success in terms of end-user acceptance and, thereafter, adoption and social impact. Widespread acceptance will not, however, be achieved if users’ interaction with mobile technology amounts to a negative experience. Mobile user interfaces need to be designed to meet the functional and sensory needs of users. Social and Organizational Impacts of Emerging Mobile Devices: Evaluating Use focuses on human-computer interaction related to the innovation and research in the design, evaluation, and use of innovative handheld, mobile, and wearable technologies in order to broaden the overall body of knowledge regarding such issues. It aims to provide an international forum for researchers, educators, and practitioners to advance knowledge and practice in all facets of design and evaluation of human interaction with mobile technologies.