Linux XIA: an interoperable meta network architecture

With the growing number of clean-slate redesigns of the Internet, the need for a medium that enables all stakeholders to participate in the realization, evaluation, and selection of these designs is increasing. We believe that the missing catalyst is a meta network architecture that welcomes most, if not all, clean-state designs on a level playing field, lowers deployment barriers, and leaves the final evaluation to the broader community. This thesis presents the eXpressive Internet (Meta) Architecture (XIA), itself a clean-slate design, as well as Linux XIA, a native implementation of XIA in the Linux kernel, as a candidate. As a meta network architecture, XIA is highly flexible, leaving stakeholders to choose an expressive set of network principals to instantiate a given network architecture within the XIA framework. Central to XIA is its novel, non-linear network addressing format, from which derive key architectural features such as evolvability, intrinsically secure identifiers, and a low degree of principal isolation. XIP, the network layer protocol of XIA, forwards packets by navigating these structured addresses and delegating the decision-making and packet processing to appropriate principals, accordingly. Taken together, these mechanisms work in tandem to support a broad spectrum of interoperable principals. We demonstrate how to port four distinct and unrelated network architectures onto Linux XIA, none of which were designed for interoperability with this platform. We then show that, notwithstanding this flexibility, Linux XIA's forwarding performance remains comparable to that of the more mature legacy TCP/IP stack implementation. Moreover, the ported architectures, namely IP, Serval, NDN, and ANTS, empower us to present a deployment plan for XIA, to explore design variations of the ported architectures that were impossible in their original form due to the requirement of self-sufficiency that a standalone network architecture bears, and to substantiate the claim that XIA readily supports and enables network evolution. Our work highlights the benefits of specializing network designs that XIA affords, and comprises instructive examples for the network researcher interested in design and implementation for future interoperability

CCD Photometry of Delta Scuti stars 7 Aql and 8 Aql

As a continuation of the study of the Delta Scuti stars 7 Aql and 8 Aql; new CCD photometric data were acquired in 2007. We present a period analysis on these data that confirm the dominant modes detected in each star in the framework of the STEPHI XII campaign in 2003.Comment: 9 pages, 7 figures, 2 tables; Accepted for publication in Communications in Asteroseismology, Vol 153, 200

Multi-site observations of Delta Scuti stars 7 Aql and 8 Aql (a new Delta Scuti variable): The twelfth STEPHI campaign in 2003

We present an analysis of the pulsation behaviour of the Delta Scuti stars 7 Aql (HD 174532) and 8 Aql (HD 174589) -- a new variable star -- observed in the framework of STEPHI XII campaign during 2003 June--July. 183 hours of high precision photometry were acquired by using four-channel photometers at three sites on three continents during 21 days. The light curves and amplitude spectra were obtained following a classical scheme of multi-channel photometry. Observations in different filters were also obtained and analyzed. Six and three frequencies have been unambiguously detected above a 99% confidence level in the range 0.090 mHz--0.300 mHz and 0.100 mHz-- 0.145 mHz in 7 Aql and 8 Aql respectively. A comparison of observed and theoretical frequencies shows that 7 Aql and 8 Aql may oscillate with p modes of low radial orders, typical among Delta Scuti stars. In terms of radial oscillations the range of 8 Aql goes from n=1 to n=3 while for 7 Aql the range spans from n=4 to n=7. Non-radial oscillations have to be present in both stars as well. The expected range of excited modes according to a non adiabatic analysis goes from n=1 to n=6 in both stars.Comment: 8 pages, 7 fugures, 5 tables, accepted for publication in Astronomical Journa

Modelagem, Análise e Proposta de Retrofit do Laboratório de Planejamento de Sistemas de Energia Elétrica

TCC (graduação) - Universidade Federal de Santa Catarina. Centro Tecnológico. Engenharia Elétrica.A busca por sistemas energeticamente eficientes tem se tornado cada vez maior, em especial no setor da construção civil. Sabe-se que atualmente as edificações representam aproximadamente 50\% de todo o consumo energético do Brasil. As edificações públicas no Brasil representam uma parcela significativa do consumo final de energia do pais. Os principais responsáveis pelo consumo energético de uma edificação são o sistema de iluminação artificial e o sistema de climatização, chegando a consumir aproximadamente 70\% do consumo total de um edifício. Dessa forma, a procura pela eficientização de edificações tem se tornado mais comum. Dentro desse panorama, este trabalho tem como objetivo realizar uma análise do atual desempenho energético do LABPLAN através de softwares de simulações energéticas além de avaliar o nível de conforto térmico e visual de seus usuários. Para atingir tal objetivo foi realizado o levantamento das informações da edificação, suas estruturas e características internas, a partir de um modelo tridimensional criado através de informações levantadas. Com base no modelo criado, foi possível avaliar a atual situação do desempenho energético do LABPLAN bem como avaliar as condições de conforto dos usuários. Além disso, através de um modelo de informação da edificação foi possível a implementação de um modelo dinâmico para criação de diversos cenários de análise e buscar melhorar as condições de utilização e sua eficiência. Uma proposta de retrofit foi sugerida, através de uma atualização dos sistemas de iluminação e climatização, sendo possível obter uma economia de aproximadamente 15\% de toda energia consumida pelo laboratório e ainda melhorar o desempenho da edificação aumentando o conforto e o bem estar de seus usuários