Vertical Bearing Capacity of a Partially-Embedded Pipeline on Tresca Soils

Slip-line field solutions are presented for the ultimate load of submarine pipelines on a purely cohesive soil obeying Tresca yield criterion, taking into account of pipe embedment and pipe-soil contact friction. The derived bearing capacity factors for a smooth pipeline degenerate into those for the traditional strip-line footing when the embedment approaches zero. Parametric studies demonstrate that the bearing capacity factors for pipeline foundations are significantly influenced by the pipeline embedment and the pipe-soil frictional coefficient. With the increase of pipeline embedment, the bearing capacity factor Nc decreases gradually, and finally reaches the minimum value (4.0) when the embedment equals to pipeline radius. As such, if the pipeline is directly treated as a traditional strip footing, the bearing capacity factor Nc would be over evaluated. The ultimate bearing loads increase with increasing pipeline embedment and pipe-soil frictional coefficient.

The South Atlantic Alliance: A southeastern U.S. state Governors initiative to address opportunities and challenges embodied in the region's coastal and ocean domain

The pressures placed on the natural, environmental, economic, and cultural sectors from continued growth, population shifts, weather and climate, and environmental quality are increasing exponentially in the southeastern U.S. region. Our growing understanding of the relationship of humans with the marine environment is leading us to explore new ecosystem-based approaches to coastal management, marine resources planning, and coastal adaptation that engages multiple state jurisdictions. The urgency of the situation calls for coordinated regional actions by the states, in conjunction with supporting partners and leveraging a diversity of resources, to address critical issues in sustaining our coastal and ocean ecosystems and enhancing the quality of life of our citizens. The South Atlantic Alliance (www.southatlanticalliance.org) was formally established on October 19, 2009 to “implement science-based policies and solutions that enhance and protect the value of coastal and ocean resources of the southeastern United States which support the region's culture and economy now and for future generations.” The Alliance, which includes North Carolina, South Carolina, Georgia, and Florida, will provide a regional mechanism for collaborating, coordinating, and sharing information in support of resource sustainability; improved regional alignment; cooperative planning and leveraging of resources; integrated research, observations, and mapping; increased awareness of the challenges facing the South Atlantic region; and inclusiveness and integration at all levels. Although I am preparing and presenting this overview of the South Atlantic Alliance and its current status, there are a host of representatives from agencies within the four states, universities, NGOs, and ongoing southeastern regional ocean and coastal programs that are contributing significant time, expertise, and energy to the success of the Alliance; information presented herein and to be presented in my oral presentation was generated by the collaborative efforts of these professionals. I also wish to acknowledge the wisdom and foresight of the Governors of the four states in establishing this exciting regional ocean partnership. (PDF contains 4 pages)

Electro-optic integration of embedded electrodes and waveguides in LiNbO3 using a femtosecond laser

We describe the fabrication of a Mach-Zehnder optical modulator in LiNbO3 by femtosecond laser micormachining, which is composed of optical waveguides inscripted by a femtosecond laser and embedded microelectrodes subsequently using femtosecond laser ablation and selective electroless plating. A half-wave voltage close to 19 V is achieved at a wavelength of 632.8 nm with an interaction length of 2.6 mm. This simple and cost-effective technique opens up new opportunities for fabricating integrated electro-optic devices. (C) 2008 Optical Society of America

Fabrication of microelectrodes deeply embedded in LiNbO3 using a femtosecond laser

We present a novel technique to fabricate deeply embedded microelectrodes in LiNbO3 using femtosecond pulsed laser ablation and selective electroless plating. The fabrication process mainly consists of four steps, which are (1) micromachining of microgrooves on the surface of LiNbO3 by femtosecond laser ablation; (2) formation of AgNO3 films on substrates; (3) scanning the femtosecond laser beam in the fabricated microgrooves for modi. cation of the inner surfaces; and (4) electroless copper plating. The void-free electroless copper plating is obtained with appropriate cross section of microgrooves and uniform initiation of the autocatalytic deposition on the inner surface of grooves. The dimension and shape of the microelectrodes could be accurately controlled by changing the conditions of femtosecond laser ablation, which in turn can control the distribution of electric field inside LiNbO3 crystal for various applications, opening up a new approach to fabricate three-dimensional integrated electro-optic devices. (C) 2008 Elsevier B. V. All rights reserved.

Analysis-aware design of embedded systems software

In the past many different methodologies have been devised to support software development and different sets of methodologies have been developed to support the analysis of software artefacts. We have identified this mismatch as one of the causes of the poor reliability of embedded systems software. The issue with software development styles is that they are ``analysis-agnostic.'' They do not try to structure the code in a way that lends itself to analysis. The analysis is usually applied post-mortem after the software was developed and it requires a large amount of effort. The issue with software analysis methodologies is that they do not exploit available information about the system being analyzed.

In this thesis we address the above issues by developing a new methodology, called "analysis-aware" design, that links software development styles with the capabilities of analysis tools. This methodology forms the basis of a framework for interactive software development. The framework consists of an executable specification language and a set of analysis tools based on static analysis, testing, and model checking. The language enforces an analysis-friendly code structure and offers primitives that allow users to implement their own testers and model checkers directly in the language. We introduce a new approach to static analysis that takes advantage of the capabilities of a rule-based engine. We have applied the analysis-aware methodology to the development of a smart home application.

Photoluminescence of Ag nanoparticle embedded Tb3+/Ce3+ codoped NaYF4/PVP nanofibers prepared by electrospinning

Ag nanoparticle embedded NaYF4:0.05Tb center dot chi Ce/ PVP (PVP stands for poly(vinyl pyrrolidone)) composite nanofibers have been prepared by electrospinning. A field emission scanning electron microscope and x-ray diffraction have been utilized to characterize the size, morphology and structure of the as-prepared electrospun nanofibers. Obvious photoluminescence (PL) of NaYF4:0.05Tb center dot 0.05Ce/PVP electrospun nanofibers due to the efficient energy transfer from Ce3+ to Tb3+ ions is observed. The PL intensity of the electrospun nanofibers decreases gradually with the addition of Ag nanoparticles. No obvious surface plasmon resonance enhanced luminescence is observed. The reasons for the weakening of the emission intensity with the addition of Ag nanoparticles have also been discussed in this work.

Real-World Social Cognition: Context Effects in Face and Threat Processing

As borne out by everyday social experience, social cognition is highly dependent on context, modulated by a host of factors that arise from the social environment in which we live. While streamlined laboratory research provides excellent experimental control, it can be limited to telling us about the capabilities of the brain under artificial conditions, rather than elucidating the processes that come into play in the real world. Consideration of the impact of ecologically valid contextual cues on social cognition will improve the generalizability of social neuroscience findings also to pathology, e.g., to psychiatric illnesses. To help bridge between laboratory research and social cognition as we experience it in the real world, this thesis investigates three themes: (1) increasing the naturalness of stimuli with richer contextual cues, (2) the potentially special contextual case of social cognition when two people interact directly, and (3) a third theme of experimental believability, which runs in parallel to the first two themes. Focusing on the first two themes, in work with two patient populations, we explore neural contributions to two topics in social cognition. First, we document a basic approach bias in rare patients with bilateral lesions of the amygdala. This finding is then related to the contextual factor of ambiguity, and further investigated together with other contextual cues in a sample of healthy individuals tested over the internet, finally yielding a hierarchical decision tree for social threat evaluation. Second, we demonstrate that neural processing of eye gaze in brain structures related to face, gaze, and social processing is differently modulated by the direct presence of another live person. This question is investigated using fMRI in people with autism and controls. Across a range of topics, we demonstrate that two themes of ecological validity — integration of naturalistic contextual cues, and social interaction — influence social cognition, that particular brain structures mediate this processing, and that it will be crucial to study interaction in order to understand disorders of social interaction such as autism.

A influência da linguagem para o raciocínio de crenças falsas em Teoria da Mente: uma análise em pacientes afásicos agramáticos

O termo Teoria da Mente diz respeito à habilidade que os seres humanos adquirem de compreender seus próprios estados mentais e os dos outros e predizer ações e comportamentos dentro de uma interação social. As principais questões da pesquisa em Teoria da Mente são: determinar qual o tipo de conhecimento que sustenta essa habilidade, qual sua origem e desenvolvimento e em que momento se manifesta. (Astington e Gopnik, 1991). Ao levar em consideração que a língua pode ser vista como instrumento da cognição (Spelke, 2003), através da qual o falante adquire suporte para o planejamento de ações, contribuindo para o desempenho de tarefas cognitivas complexas (Corrêa, 2006), de Villiers (2004, 2005, 2007 e subsequentes), no que diz respeito à Teoria da Mente, argumenta que o seu desenvolvimento depende do desenvolvimento linguístico, estando diretamente ligado à aquisição de verbos de estado mental, como pensar, por exemplo, pelo fato de que esses verbos subcategorizam uma sentença encaixada. Para ela, o domínio dessa estrutura possibilita que o raciocínio de crenças falsas da Teoria da Mente seja efetivamente realizado. A presente dissertação tem como objetivo verificar em que medida há uma influência direta e necessária da linguagem para a condução de tarefas de Teoria da Mente. Para tanto, focamos nossa atenção em pessoas que estão, por algum motivo, destituídas parcialmente da capacidade linguística, mas que mantêm intacta a capacidade cognitiva, os afásicos. Por meio de uma pesquisa realizada com dois pacientes afásicos de Broca, selecionados pelos critérios clássicos, procuramos entender se a habilidade de predizer ações está intacta nestes pacientes ou se tal habilidade foi perdida, assim como a linguagem. Para tanto, aplicamos dois testes de crença falsa em Teoria da Mente. O primeiro utilizou-se de suporte verbal, uma narração de eventos e expectativas dos personagens envolvidos. A pergunta-teste foi manipulada em função do grau de complexidade por meio do cruzamento de dois fatores: sentenças simples ou complexas e QU-in situ ou movido. O segundo teste seguiu o padrão não-verbal, sendo constituído de uma sequência de imagens, sendo que o sujeito deveria decidir entre duas últimas imagens apresentadas, aquela que coerentemente finalizava a história. Uma vez que houvesse influência direta da linguagem na condução de tarefas de Teoria da Mente, esperar-se-ia que a dificuldade no teste verbal refletisse o grau de complexidade das questões apresentadas. Adicionalmente, o desempenho no teste não-verbal também deveria ser insatisfatório, dado o comprometimento linguístico apresentado pelos sujeitos testados. Para o primeiro teste, o desempenho dos pacientes foi aleatório e inferior ao do grupo controle, já para o segundo teste, o aproveitamento foi de 100%. Em geral, os resultados sugerem que o raciocínio de crenças falsas em Teoria da Mente é alcançado por esses sujeitos, haja vista o desempenho plenamente satisfatório no teste não-verbal. Os resultados do teste verbal, por outro lado, atestam tão somente a dificuldade linguística característica dessa população. Desse modo, conclui-se que uma vez desenvolvida a habilidade em Teoria da Mente, esta permanece intacta na mente destes pacientes, mesmo que destituídos parcialmente da capacidade linguística

An Embedded Stress Sensor for Concrete SHM Based on Amorphous Ferromagnetic Microwires

A new smart concrete aggregate design as a candidate for applications in structural health monitoring (SHM) of critical elements in civil infrastructure is proposed. The cement-based stress/strain sensor was developed by utilizing the stress/strain sensing properties of a magnetic microwire embedded in cement-based composite (MMCC). This is a contact-less type sensor that measures variations of magnetic properties resulting from stress variations. Sensors made of these materials can be designed to satisfy the specific demand for an economic way to monitor concrete infrastructure health. For this purpose, we embedded a thin magnetic microwire in the core of a cement-based cylinder, which was inserted into the concrete specimen under study as an extra aggregate. The experimental results show that the embedded MMCC sensor is capable of measuring internal compressive stress around the range of 1-30 MPa. Two stress sensing properties of the embedded sensor under uniaxial compression were studied: the peak amplitude and peak position of magnetic switching field. The sensitivity values for the amplitude and position within the measured range were 5 mV/MPa and 2.5 mu s/MPa, respectively.