1,790 research outputs found
Linda Talk : suporte distribuido a programação concorrente orientada a objetos
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro TecnologicoProblemas complexos são geralmente decompostos em subproblemas menores, que sejam tratáveis mais facilmente. O mesmo vale para sistemas de computação, os quais contam com uma gama rica de abordagens de decomposição (funcional, procedural, etc). Dentre estas, a decomposição orientada a objetos tem ganho cada vez mais espaço, dada sua riqueza e poder na modelagem e implementação de sistemas informáticos. A possibilidade de programar sistemas multiprocessadores e sistemas em redes de computadores, por outro lado, favoreceu as linhas de programação paralela/concorrente/distribuída. Contudo, se de um lado a orientação a objetos clássica promove uma modelagem natural de entidades no domínio do problema, por outro lado ela falha na tentativa de expressar atividades concorrentes/paralelas. Já sistemas que suportam a noção de processos paralelos, tais como Occam, Conic, Ada, etc, permitem preencher esta lacuna. Contudo, o poder de modelagem e abstração de entidades fica bastante limitado neste tipo de abordagem, levandogeralmente à produção de sistemas difíceis de adaptar, manter e recusar. Modelos com suporte à programação paralela orientada a objetos, tais como Emerald, ConcurrentSmalltalk, Act-1, ABCL/1, etc. surgem na tentativa de unificar objetos no sentido clássico de orientação a objetos com a noção de processos paralelos e comunicantes. Porém, tanto nesta abordagem quanto na programação orientada a objetos clássica e alguns modelos de programação concorrente/paralela/distribuída, a metófora de interação entre objetos/processo é a mesma: troca de mensagens. Troca de mensagens conforme presente em sistemas concorrentes orientados a objetos apresentam diversas fraquezas no que toca a implementação, manutenção e reusabilidade de sistemas distribuídos. Nossa proposta busca incorporar a uma linguagem orientada a objetos clássica - Smalltalk - um modelo que suporte a programação paralela/distribuída com um maior grau de flexibilidade. Este modelo é o de Espaço de Tuplas, de Linda. Através de um pequeno conjunto de primitivas, tem-se um modelo simples de criação e coordenação de processos ortogonal à linguagem em que se insere o modelo (Smalltalk, no caso). Através do uso extensivo do modelo, acreditamos ser possível a construção de sistemas realmente distribuídos e orientados a objetos com um maior grau de flexibilidade em sua implementação, reusabilidade e manutenção
Scanning Tunneling Microscopy and Spectroscopy investigations of Graphene on Ru(0001) and (CO+O) on Rh(111)
No full textTemperature analysis of the water supply system of a dairy company by means of a simulation model
No full textThis paper describes the second part of a research project that examined, by means of simulation, the water distribution system of a dairy company located near Parma (Italy) and active for decades in the production of Parmigiano Reggiano cheese and butter. The first part of the research was described by Marchini et al. (2013) and focused on finding opportunities for recycling water in the distribution system of the dairy company considered. In this work, we go ahead by analyzing the thermal properties (such as, primarily, the temperature) of the water used inside the distribution system, as well as of that discharged. Specifically, the aim of the present study is to estimate the water temperature into each tank of the plant. To achieve this aim, we build upon the MS ExcelTM simulation model developed by Marchini et al. (2013) and add the related thermal equations. As a result, we define the temperature trend of water inside all the tanks of the distribution system. Situations where the water temperature is higher than the boundary defined by the company (i.e., approx. 25°C) are also highlighted
"GA-banding": a new terminology and a study of the glutaraldehyde-induced band pattern of type I collagen fibrils
No full textThe negative staining D-band patterns of glutaraldehyde-reacted collagen fibrils were compared to those of fresh collagen fibrils. Negative staining was obtained by using 1% phosphotungstic acid (PTA) diluted in phosphate buffer 0.1 M, pH 7.4. The stain was dripped onto grids where native type I collagen fibrils, isolated from bovine dermis, were collected. Ultrastructural pictures were digitized to form microdensitometric traces. The glutaraldehyde-induced patterns showed fifteen light bands (micrographs) or negative peaks (microdensitograms), whose D-locations were constant and characteristic. In order to make this ultrastructural feature a precise reference parameter, these bands were called "GA-bands" and numbered. When comparing this averaged microdensitogram with that of negatively stained fresh fibrils, peak "GA1" and peak "GA7" were observed to correspond to peak "X2" (known as N-terminal telopeptide region) and peak "X3" (known as C-terminal telopeptide region) respectively, while there was no correspondence between the other peaks of the two traces. It means that the regions where preexistent crosslinks exist are unaffected by interaction with glutaraldehyde, while in the other regions, where new glutaraldehyde-crosslinks occur, the band pattern modifies. The unchanged D-location of peaks "GA1" and "GA7" leads to the conclusion that the D-shortening induced by glutaraldehyde is not due to shifting of tropocollagen molecules but to changes in their orientation with respect to fibril long axis or in secondary-tertiary structure of collagen
Understanding care relationships in diabetes practice: A psychodynamic interview-based exploratory study
No full textObjective To explore the subjective experience of physicians working in diabetic settings about their care relationships in order to find some unique clues contributing to physician professional health and capacity to manage patients’ adherence. Research design and methods An interview-based exploratory study has been carried out involving 18 physicians (77.8% female) with at least 3 years of clinical practice in diabetes care. In-depth interviews about the emotional experience with patients with diabetes were conducted and audio recorded. Interviews transcripts were analyzed through a computer-based text analysis which allowed the identification of thematic domains (Cluster Analysis) and latent factors (Correspondence Analysis) viewed through a psychodynamic and constructivist lens. Results Six thematic domains emerged respectively referring to: Concern (8.43%), Control (14.42%), Ambivalence (22.08%), Devotion (22.49%), Guilt (19.29%) and Strive for Achievement (13.30%). Moreover, three latent dimensions were taken into account, which explained 69.20% of data variance: Affect Repression (28.50%), Tendency to Repair (22.70%) and Anxiety Pattern (18.00%). Conclusions Overall, the results of the present study confirm the challenging nature of diabetes care. In particular, physicians ongoing effort to restore patients’ psychological integrity in chronic condition constitute the most novel finding above all. In this regard, the need for emotional labor in physicians’ education and training is suggested in order to both prevent burnout symptoms (e.g. depersonalization) and promote shared decision making in care relationships. However, findings should be treated as preliminary given the convenience nature of the sample and its reduced size. Copyright: © 2022 Marchini et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
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