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匹配条件: “Carolina;” ,找到相关结果约8174条。
Vibrations of a One-Dimensional Host-Guest System  [PDF]
Amelia Carolina Sparavigna
Materials Sciences and Applications (MSA) , 2011, DOI: 10.4236/msa.2011.25041
Abstract: A simple model shows how it is possible to create a gap in the vibrational spectrum of a one-dimensional lattice. The proposed model is a host-guest chain having, instead of point-like masses connected by spring, massive cages hosting particles inside. We imagine the cage as a rigid box containing a mass linked by a spring to the box inner wall. The presence of guests creates an energy gap in the dispersion of vibrational frequencies. The gap is about the internal resonance of the mass hidden in the cage. The model is proposed to help understanding the macroscopic behaviour of some phononic materials and the properties of materials with microscopic rattling modes.
Measuring the Thermal Diffusivity in a Student Laboratory  [PDF]
Amelia Carolina Sparavigna
Engineering (ENG) , 2012, DOI: 10.4236/eng.2012.45035
Abstract: The paper describes a method for measuring the thermal diffusivity of materials having a high thermal conductivity. The apparatus is rather simple and low-cost, being therefore suitable in a laboratory for undergraduate students of engineering schools, where several set-ups are often required. A recurrence numerical approach solves the thermal field in the specimen, which is depending on the thermal diffusivity of its material. The numerical method requires the temperature data from two different positions in the specimen, measured by two thermocouples connected to a temperature logger.
An Ancient Rangefinder for Teaching Surveying Methods  [PDF]
Amelia Carolina Sparavigna
Engineering (ENG) , 2012, DOI: 10.4236/eng.2012.49073
Abstract: Rangefinders are instruments used for ballistics and for surveying in general. Here we propose a discussion of some of them, ranging from the ancient Rome to the modern methods. Using an ancient roman artefact as a model, we can prepare a rangefinder at no cost for teaching surveying methods to students of engineering and military schools.
Youth and Social Security Coverage in Brazil  [PDF]
Paulo Tafner, Carolina Botelho
Open Journal of Social Sciences (JSS) , 2014, DOI: 10.4236/jss.2014.21014
Abstract: Brazil is still a young country, just starting the process of aging, but Brazils spending on social security is similar to those countries whose population aging has already occurred. Some studies explain the high cost of the Brazilian Social Security System due to the assumption that there is a positive relationship between social security and poverty alleviation. In fact, the effectiveness of this instrument as reducing poverty was high until 2002, but stopped growing and fell slightly thereafter. Brazilian law provides that wives and children or stepchildren under age 21, or under 25, since they are college students, are welfare beneficiaries. In other words they are protected by Brazilian Social Security System. However, data reveals that in Brazil, children and young people have a very low social security direct coverage, which increases with age and reaches high levels for individuals aged 60 or older. Children and young people are the groups most affected by poverty and extreme poverty in Brazil. In this sense, the assumption according to which Social Security helps combat family poverty is flawed. Considering these issues, this article aims to contribute to the debate on the need to rethink the Brazilian Social Security System and the need of construction of specific policies for children and young people in Brazil.
Role of Plasma Surface Treatments on Wetting and Adhesion  [PDF]
Rory Wolf, Amelia Carolina Sparavigna
Engineering (ENG) , 2010, DOI: 10.4236/eng.2010.26052
Abstract: There are many current and emerging wetting and adhesion issues which require an additional surface processing to enhance interfacial surface properties. Materials which are non-polar, such as polymers, have low surface energy and therefore typically require surface treatment to promote wetting of inks and coating. One way of increasing surface energy and reactivity is to bombard a polymer surface with atmospheric plasma. When the ionized gas is discharged on the polymer, effects of ablation, crosslinking and activation are produced on its surface. In this paper we will analyse the role of plasma and its use in increasing the surface energy to achieve wettability and improve adhesion of polymeric surfaces.
Anticipation of Traffic Demands to Guarantee QoS in IP/Optical Networks
Carolina Pinart
Future Internet , 2010, DOI: 10.3390/fi2030417
Abstract: Traffic in the Internet backbone is expected to grow above a few Tbit/s in 2020. To cope with this, operators are moving to IP/optical network architectures, where IP is the convergence layer for all services. On the other hand, the quality of service (QoS) requirements of future applications encompasses the individualization of services and the assurance of stricter quality parameters such as latency, jitter or capacity. In other words, future optical networks will not only transport more IP data, but they will also have to offer differentiated QoS requirements to services. Finally, some emerging applications, e.g., grid computing, need greater flexibility in the usage of network resources, which involves establishing and releasing connections as if they were virtualized resources controlled by other elements or layers. In this context, traffic-driven lightpath provisioning and service-plane approaches arise as very interesting candidate solutions to solve the main challenges described above. This work reviews the concepts of service-oriented and self-managed networks and relates them to propose an integrated approach to assure QoS by offering flow-aware networking in the sense that traffic demands will be anticipated in a suitable way, lightpaths will be established taking into account QoS information ( i.e., impairments) and complex services will be decomposed into optical connections so that the above techniques can be employed to assure QoS for any service.
Plantas transformables: La vivienda colectiva como objeto de intervención
ARQ (Santiago) , 2004, DOI: 10.4067/S0717-69962004005800022
Abstract: the ground plan may be understood as the genetic material of space, and though it is not able to specify which acts will occur in it, it is very precise in indicating which ones cannot. in collective housing, the problem that cannot be solved by a standard floor plan is obvious. new questions about typologies, construction and building strategies are raised by the search for floor plans that are capable of change, driven by the rise of unpredictable new family arrangements and the waning of traditionally dominant social patterns.
Países Bajos, territorio reversible
ARQ (Santiago) , 2009, DOI: 10.4067/S0717-69962009000200015
Abstract: the low countries? experience with control of land and water is extensive. its inhabitants possess comprehensive knowledge of its characteristics, dynamically interacting with their habitat. however, environmental and economic needs have required the review and even the reversal of this complex hydraulic system.
Capital social: premisas, problemas y perspectivas teóricas
EPISTEME , 2006,
Abstract: the theory of social capital is an innovating approach directed to understand the essential aspects of modern democratic systems as the functioning of the institutions responsible of the rules of the game in a society. this theory was initiated by the north american researches, robert d. putnam, who argues that an institution with highly effective performance depends mainly on the civic traditions in the culture that characterizes the society in which it operates, since it is through civic traditions that peoples and institutions develop mechanisms and resources which affect in a determining way the fulfillment of the rules of social games. we are interested in studying the issues concerning putnam?s notion of social capital, analyzing its achievements, scope constraints and difficulties. at the same time, we will suggest some theoretical considerations that could enrich research in this important topic.
O gosto dominante como gosto tradicional: preferências e avers?es estéticas das classes altas de S?o Paulo
Pulici, Carolina;
Novos Estudos - CEBRAP , 2011, DOI: 10.1590/S0101-33002011000300007
Abstract: based on semi-directive interviews with wealthy people groups of s?o paulo and on cultural critics from this city's contemporary press, this article discusses some visions that bankers, art collectors, ambassadors, farmers, rentiers, philanthropists, entrepreneurs, powerful businessmen, industrialists, etc. create of themselves and of the other groups through their manifest aesthetical preferences. the analysis of their preferences in architecture, cinema and paintings indicates a general lack of vanguard taste.

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