Intensity-modulating characteristics of a laser diode subjected to optical injection

We have found that the optical power of a laser diode (LD) does not change with the injected light intensity that is modulated when its injection current is at some specific values. The amplitude of optical power change of the LD varies periodically with the increase of the injection current. It is made clear through theoretical analysis that these phenomena are caused by gain compression and interband carrier absorption of the LD that depend on longitudinal mode competition, bandgap-shrinkage effects, thermal conduction, and so on. Our experimental results make it easy to eliminate optical power change of LDs. We only need to choose a proper value of the injection current. (c) 2005 Optical Society of America.

A judicialização das políticas públicas de telecomunicações e as demandas dos consumidores: o impacto da ação judicial

A tese parte da seguinte hipótese: a intervenção judicial possibilita a alteração das políticas regulatórias, tendo por base o caso das telecomunicações no Brasil. O primeiro capítulo descreve o processo de privatização do setor regulado e a formação de um novo ambiente empresarial, com destaque para a organização de um sistema legal e regulamentar para possibilitar o funcionamento do novo sistema. O segundo capítulo mostra como é formada a doutrina jurídica, no campo do Direito Administrativo, que serviu de junção para o novo setor empresarial e as instituições regulatórias que surgiram, denominadas agências reguladoras. O terceiro capítulo focaliza a construção institucional das agências reguladoras, bem como os dilemas institucionais que a acompanharam. O quarto capítulo resenha o debate teórico sobre a judicialização da política, com foco nas políticas públicas, bem como analisa as ações diretas de inconstitucionalidade, ajuizadas com o objetivo de paralisar a privatização. O quinto capítulo detalha a insurgência dos consumidores, em um movimento de base que permitiu a alteração regulamentar no topo. O último narra o Projeto Expressinho, uma proposta para o estabelecimento desta seara jurisdicional por um meio alternativo de resolução de conflitos. As considerações finais evidenciam que foram introduzidas características do modelo de direito responsivo, que é descrito por Nonet e Selnick. A conclusão é que os traços de responsividade no sistema político e judicial brasileiro tendem a aprofundar este tipo de intervenção, tendo se mostrado como um canal mais efetivo para a permeabilidade social do que o eram as propaladas audiências e consultas públicas.

Análise dos Modos de Plasmon em Fibras Ópticas com Contraste Arbitrário de Índices de Refração.

Neste trabalho, é feita a análise dos modos de plasmon que se propagam em um filme metálico que cobre uma fibra óptica generalizada. Os modos de plasmon estudados são: Fuga pela Cobertura (lcv), Ligado Simétrico (Sb), Fuga pelo Núcleo (lcr) e Ligado Assimétrico (ab). Os filmes metálicos, para efeito de comparação, utilizados neste trabalho, são: a prata, o ouro e o paládio. Desenvolveu-se um modelo matemático do fenômeno eletromagnético e um software, que gerou um banco de dados que facilitasse a análise de estruturas, com diversas combinações de parâmetros. Com o banco de dados, foram obtidos diversos gráficos, que permitiram: analisar os modos de plasmon, verificar a atenuação das ondas e o comportamento do campo eletromagnético em cada região da estrutura. As confrontações entre as estruturas com filmes de: prata, ouro e paládio, permitiram concluir que aquelas elaboradas com os filmes de prata e de ouro são as que apresentam menores perdas, portanto, as recomendadas na confecção de sensores. Como a prata é mais acessível que o ouro, aconselha-se a sua utilização. A análise e os resultados deste trabalho são originais na literatura especializada.

The diversity of amphibians, reptiles and mammals and their importance in the Victoria and Kyoga lake basins

The shore margins of Lakes in the Victoria basin are highly dented and mostly swampy, fringed by Papyrus and other wetland vegetation types important habitats for herpetofauna and wetland adapted mammals. Of recent, the extent of the 'wetland' has been extended in several places by the Water Hyacinth (Eichornia cryaseps). Ecologically, amphibians are important in many ways; they are mostly predators, acting as primary and secondary carnivores. Their prey consists mostly of insects, some of which are pests to crops or disease vectors. They are also inter-inked in food chains, often acting as food for other vertebrates, such as pigs, birds, snakes and sometimes man. Because of their ectothermic physiology, the life history and ecology of amphibians often differ markedly from that of birds or mammals (McCollough el ai, (992).Amphibians are known to be an easily recognisable taxon in given habitats; and populations are sometimes specialised within a narrow habitat. This makes it easy and practical to monitor changes in composition over time, given different onditions (Heyer el al 1994, Phillips 1990). Impacts on their habitat are reflected in changes in numbers and species diversity in a short time. These are some of the factors that have made amphibians to be recognised, nowadays, as good indicators of habitat change

PATTERNS OF SPATIAL-DISPERSION, LOCOMOTION AND FORAGING BEHAVIOR IN 3 GROUPS OF THE YUNNAN SNUB-NOSED LANGUR (RHINOPITHECUS-BIETI)

Aspects of the behaviour of three groups of Yunnan snub-nosed langurs, Rhinopithecus bieti, were observed over the course of three field seasons from 1986 to 1988. The major findings of the study were: (1) The habitats of R. bieti were mainly at heights of 3,600-4,150 m above sea level. (2) Groups were very large, with group sizes ranging from more than 100 to 269 individuals. (3) Spatial dispersion densities ranged from about 27 to 106 m2/individual during sleeping and resting, to feeding dispersions as large as 5,000-15,000 m2. (4) The locomotor repertoire of R. bieti consisted largely of walking, jumping and climbing. On very rare occasions, semibrachiation was observed, but true brachiation was never observed. The locomotor repertoires of juveniles were more diverse than those of subadults or adults. (5) Communication consisted mainly of eye-to-eye contact accompanied by murmurs; while loud calls were heard only rarely. (6) Groups moved between sleeping and feeding sites in single file. It is concluded that R. bieti is a mainly terrestrial species.

Shape-Based Retrieval of Construction Site Photographs

Digital photographs of construction site activities are gradually replacing their traditional paper based counterparts. Existing digital imaging technologies in hardware and software make it easy for site engineers to take numerous photographs of “interesting” processes and activities on a daily basis. The resulting photographic data are evidence of the “as-built” project, and can therefore be used in a number of project life cycle tasks. However, the task of retrieving the relevant photographs needed in these tasks is often burdened by the sheer volume of photographs accumulating in project databases over time and the numerous objects present in each photograph. To solve this problem, the writers have recently developed a number of complementary techniques that can automatically classify and retrieve construction site images according to a variety of criteria (materials, time, date, location, etc.). This paper presents a novel complementary technique that can automatically identify linear (i.e., beam, column) and nonlinear (i.e., wall, slab) construction objects within the image content and use that information to enhance the performance of the writers’ existing construction site image retrieval approach.

Assignment of absolute configuration of cyclic secondary amines by NMR techniques using Mosher's method: a general procedure exemplified with (-)-isoanabasine

A general procedure to determine the absolute configuration of cyclic secondary amines with Mosher's NMR method is demonstrated, with assignment of absolute configuration of isoanabasine as an example. Each Mosher amide can adopt two stable conformations (named rotamers) caused by hindered rotation around amide C-N bond. Via a three-step structural analysis of four rotamers, the absolute configuration of (-)-isoanabasine is deduced to be (R) on the basis of Newman projections, which makes it easy to understand and clarify the application of Mosher's method to cyclic secondary amines. Furthermore, it was observed that there was an unexpected ratio of rotamers of Mosher amide derived from (R)-isoanabasine and (R)-Mosher acid. This phenomenon implied that it is necessary to distinguish the predominant rotamer from the minor one prior to determining the absolute configuration while using this technique.

The electrochemical behavior of colloidal polypyrrole

The electrochemical behavior and charge transport of colloidal polypyrrole particles (without stabilizer) modified electrode have been investigated. The voltametric results show that the electrochemical behavior of colloidal polypyrrole is different from that of polypyrrole synthesized electrochemically. The strong adsorption of the colloidal particles on substrate makes it easy to form a polypyrrole modified electrode. The charge transport of polypyrrole is controlled by the diffusion of counterions.

How do Humans Determine Reflectance Properties under Unknown Illumination?

Under normal viewing conditions, humans find it easy to distinguish between objects made out of different materials such as plastic, metal, or paper. Untextured materials such as these have different surface reflectance properties, including lightness and gloss. With single isolated images and unknown illumination conditions, the task of estimating surface reflectance is highly underconstrained, because many combinations of reflection and illumination are consistent with a given image. In order to work out how humans estimate surface reflectance properties, we asked subjects to match the appearance of isolated spheres taken out of their original contexts. We found that subjects were able to perform the task accurately and reliably without contextual information to specify the illumination. The spheres were rendered under a variety of artificial illuminations, such as a single point light source, and a number of photographically-captured real-world illuminations from both indoor and outdoor scenes. Subjects performed more accurately for stimuli viewed under real-world patterns of illumination than under artificial illuminations, suggesting that subjects use stored assumptions about the regularities of real-world illuminations to solve the ill-posed problem.

Improving the Accessibility of Lightweight Formal Verification Systems

In research areas involving mathematical rigor, there are numerous benefits to adopting a formal representation of models and arguments: reusability, automatic evaluation of examples, and verification of consistency and correctness. However, broad accessibility has not been a priority in the design of formal verification tools that can provide these benefits. We propose a few design criteria to address these issues: a simple, familiar, and conventional concrete syntax that is independent of any environment, application, or verification strategy, and the possibility of reducing workload and entry costs by employing features selectively. We demonstrate the feasibility of satisfying such criteria by presenting our own formal representation and verification system. Our system’s concrete syntax overlaps with English, LATEX and MediaWiki markup wherever possible, and its verifier relies on heuristic search techniques that make the formal authoring process more manageable and consistent with prevailing practices. We employ techniques and algorithms that ensure a simple, uniform, and flexible definition and design for the system, so that it easy to augment, extend, and improve.

SELECTED ICONIC CHAMBER MUSIC WORKS WITH PIANO FROM THE NINETEENTH AND TWENTIETH CENTURIES

Chamber music repertoire featuring the piano blossomed from the mid-nineteenth through the early twentieth century. The quantity of works increased greatly during this time and the quality of these works reached the highest level. Among the many symbolic works that were composed were sonatas for a single string instrument with piano, piano trios, quartets: and quintets as well as two-piano works and four-hand duets. Being able to study and perform many of these iconic works before I graduated was one of the major goals I set for myself as a collaborative pianist. The abundance of repertoire has made it easy to choose works considered "iconic" for my dissertation's three recitals. Iconic is defined as "very famous or popular, especially being considered to represent particular opinions or a particular time" in the online Cambridge Advanced Leamer's Dictionary & Thesaurus © Cambridge University. The compositions featured in the recitals were composed from 1842 through 1941, including works by Schumann, Brahms, Faure, Rachmaninoff, Ravel, and Lutoslawski. Choosing the repertoire with my fellow performers in mind was an important part of this dissertation. In addition to trying to make balanced programs which include variety, working with different instruments and performers is one of the most fulfilling parts of the musical experience for me as a collaborative pianist. Joining me for the concerts were members of the Aeolus String Quartet (violinist Nicholas Tavani, violinist Rachel Shapiro, violist Greg Luce, and cellist Alan Richardson), pianist Hsiao-Ying Lin (a doctoral student from the Peabody Conservatory), and my colleagues from the Peabody Institute Preparatory Division (faculty violinist Dr. Christian Tremblay and cellist Alicia Ward), and Derek Smith, Associate Principal violist of the Annapolis Symphony Orchestras). The three recitals were performed in the Gildenhom and Ulrich Recital Halls at the University of Maryland, College Park, Maryland. They are recorded on CD and available on compact discs, which can be found in the Digital Repository at the University of Maryland (DRUM).

A Research Guide for Health & Clinical Psychology

This must-have, practical guide for trainee psychologists working towards their British Psychological Society (BPS) qualification in either health psychology or clinical psychology is designed to address the key concerns and questions that students often have when applying research designs in real settings.

The book:

- looks specifically at what is required to demonstrate research competence for the qualifications;
- is structured around a simple question-and-answer format, making it easy to navigate;
- is packed full of tips, including on ethical considerations and conducting qualitative and quantitative research designs; and
- uses health and clinical psychology research examples to highlight key issues for trainees.

Advanced educational parallel DSP system based on TMS320C25 processors

This paper describes the design, application, and evaluation of a user friendly, flexible, scalable and inexpensive Advanced Educational Parallel (AdEPar) digital signal processing (DSP) system based on TMS320C25 digital processors to implement DSP algorithms. This system will be used in the DSP laboratory by graduate students to work on advanced topics such as developing parallel DSP algorithms. The graduating senior students who have gained some experience in DSP can also use the system. The DSP laboratory has proved to be a useful tool in the hands of the instructor to teach the mathematically oriented topics of DSP that are often difficult for students to grasp. The DSP laboratory with assigned projects has greatly improved the ability of the students to understand such complex topics as the fast Fourier transform algorithm, linear and circular convolution, the theory and design of infinite impulse response (IIR) and finite impulse response (FIR) filters. The user friendly PC software support of the AdEPar system makes it easy to develop DSP programs for students. This paper gives the architecture of the AdEPar DSP system. The communication between processors and the PC-DSP processor communication are explained. The parallel debugger kernels and the restrictions of the system are described. The programming in the AdEPar is explained, and two benchmarks (parallel FFT and DES) are presented to show the system performance.

Access and information behaviour of European Documentation Centres users in Portugal and Spain: a comparative study

The aim of this study was to undertake a comparative analysis of the practices and information behaviour of European information users who visit information units specialising in European information in Portugal and Spain. The study used a quantitative methodology based on a questionnaire containing closed questions and one open question. The questions covered the general sociological profile of the respondents and their use of European Document Centres, in addition to analysing aspects associated with information behaviour relating to European themes. The study therefore examined data on the preferred means and sources for accessing European information, types of documents and the subjects investigated most. The use of European databases and the Internet to access material on Europe was also studied, together with the reasons which users considered made it easy or difficult to access European information, and the aspects they valued most in accessing this information. The questionnaire was administered in European Document Centres in 2008 and 2010.

Caractérisation de l’ubiquitin-fold modifier (UFM1) dans un modèle C. elegans

L’ubiquitin-fold modifier (UFM1) fait partie de la classe 1 de la famille de protéine ubiquitin-like (Ubl). UFM1 et Ub ont très peu d’homologie de séquence, mais partagent des similarités remarquables au niveau de leur structure tertiaire. Tout comme l’Ub et la majorité des autres Ubls, UFM1 se lie de façon covalente à ses substrats par l’intermédiaire d’une cascade enzymatique. Il est de plus en plus fréquemment rapporté que les protéines Ubls sont impliquées dans des maladies humaines. Le gène Ufm1 est surexprimé chez des souris de type MCP développant une ischémie myocardique et dans les îlots de Langerhans de patients atteints du diabète de type 2. UFM1 et ses enzymes spécifiques, UBA5, UFL1 et UFC1, sont conservés chez les métazoaires et les plantes suggérant un rôle important pour les organismes multicellulaires. Le Caenorhabditis elegans est le modèle animal le plus simple utilisé en biologie. Sa morphologie, ses phénotypes visibles et ses lignées cellulaires ont été décrits de façon détaillée. De plus, son cycle de vie court permet de rapidement observer les effets de certains gènes sur la longévité. Ce modèle nous permet de facilement manipuler l’expression du gène Ufm1 et de mieux connaître ses fonctions. En diminuant l’expression du gène ufm-1 chez le C.elegans, par la technique de l’ARN interférence par alimentation, nous n’avons observé aucun problème morphologique grave. Les vers ressemblaient aux vers sauvages et possédaient un nombre de progéniture normal. Cependant, les vers sauvage exposés à l’ARNi d’ufm-1 vivent significativement moins longtemps que les contrôles et ce, de façon indépendante de la voie de signalisation de l’insuline/IGF. Chez le C. elegans la longévité et la résistance au stress cellulaire sont intimement liées. Nous n’avons remarqué aucun effet d’ufm-1 sur le stress thermal, osmotique ou oxydatif, mais il est requis pour la protection contre le stress protéotoxique. Il est également nécessaire au maintien de l’intégrité neuronale au cours du vieillissement des animaux. L’ensemble de nos données nous renseigne sur les fonctions putatives du gène Ufm1.