335 research outputs found
A Framework for Service-Oriented Architecture (SOA)-Based IoT Application Development
Funding: This research was partially supported by funds provided by the European Commission in the scope of FoF/H2020-723710 vf-OS, ICT/H2020-825631 ZDMP projects, and by the FCT— Fundação para a Ciência e a Tecnologia in the scope of UIDB/00066/2020 related to CTS—Centro de Tecnologia e Sistemas research unit.In the last decades, the increasing complexity of industrial information technology has led to the emergence of new trends in manufacturing. Factories are using multiple Internet of Things (IoT) platforms to harvest sensor information to improve production. Such a transformation contributes to efficiency growth and reduced production costs. To deal with the heterogeneity of the services within an IoT system, Service-Oriented Architecture (SOA) is referred to in the literature as being advantageous for the design and development of software to support IoT-based production processes.The aim of SOA-based design is to provide the leverage to use and reuse loosely coupled IoT services at the middleware layer to minimise system integration problems. We propose a system architecture that follows the SOA architectural pattern and enables developers and business process designers to dynamically add, query or use instances of existing modular software in the IoT context. Furthermore, an analysis of utilization of modular software that presents some challenges and limitations of this approach is also in the scope of this workpublishersversionpublishe
Density of the reference Ionic liquid [C6mim][NTf2] at high pressures
Workshop realizado em Lisboa de 2-3 Fevereiro de 2012Density of the ionic liquid [C6mim][NTf2] – a reference ionic liquid for thermophysical properties, as proposed by IUPAC8 was measured using an Anton Paar density meter DMA HP. The basic experimental setup was described previously, and the modifications introduced in order to avoid water contamination of the sample are
described in the presentation. The measurements were performed in the temperature
range (283.15 ≤ T ≤ 353.15) K and at pressures (0.1 ≤ p ≤ 65) MPa. The water content of
the samples was measured by Karl-Fisher coulometry, both before and after the
measurements. As the viscosity of that ionic liquid is much higher than the viscosity of the
fluids used in the calibration of the densimeter, a correction of the results became
necessary, to account for the consequent error in the period of oscillation of the U-tube.
For this purpose, the viscosity effect on the density measurements on the Anton Paar DMA HP was quantified using the viscosity standard specimen (200GW) from ZMK, GmbH. The experimental determination of the viscosity correction to the measured density is described and also the preliminary results of the density of [C6mim][NTf2] are compared with literature values
High-viscosity reference liquids at high pressures
Encontro realizado no Porto a 31 de agosto de 201
Viscosity measurements on Ionic liquids : a cautionary tale
The vibrating-wire viscometer has proven to be an exceedingly effective
means of determining the viscosity of liquids over a wide range of temperature and
pressure. The instrument has a long history but a variety of technological and theoretical
developments over a number of years have improved its precision and most
recently have enabled absolute measurements of high accuracy. However, the nature
of the electrical measurements required for the technique has inhibited its widespread
use for electrically conducting liquids so that there have been only a limited number
of measurements. In the particular context of ionic liquids, which have themselves
attracted considerable attention, this is unfortunate because it has meant that one primary
measurement technique has seldom been employed for studies of their viscosity.
In the last 2 years systematic efforts have been made to explore the applicability of
the vibrating-wire technique by examining a number of liquids of increasing electrical
conductivity. These extensions have been successful. However, in the process we have
had cause to review previous studies of the viscosity and density of the same liquids
at moderate temperatures and pressures and significant evidence has been accumulated
to cause concern about the application of a range of viscometric techniques to
these particular fluids. Because the situation is reminiscent of that encountered for
a new set of environmentally friendly refrigerants at the end of the last decade, in
this paper the experimental methods employed with these liquids have been reviewed
which leads to recommendations for the handling of these materials that may have consequences beyond viscometric measurements. In the process new viscosity and
density data for 1-hexyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide
[C6mim][NTf2], 1-ethyl-3-methylimidazolium ethyl sulfate [C2mim][EtSO4], and
1-ethyl-3-methylpyridinium ethyl sulfate [C2mpy][EtSO4] have been obtained
Neck fluid extravasation in shoulder arthroscopic surgery-a life-threatening complication: a report of two cases
Fluid extravasation in shoulder arthroscopy may lead to life-threatening consequences, such as airway compromise. These cases are rare and few were reported in the literature. Clinical cases of 2 female patients submitted to shoulder arthroscopy for a rotator cuff tear repair, complicated with fluid extravasation that led to trachea compression and need for intensive care unit (ICU) admission with postponed extubation. Neither patients showed any sequelae in the follow-up period. Report of these rare complications, with detailed and reproducible information, is vital for their comprehension and future elaboration of surveillance and treatment guidelines
Dynamic Interdomain Network Slicing for verticals in the 5Growth project
Proceedings of: IEEE Conference on Network Function Virtualization and Software Defined Networks (NFV-SDN), 9-11 Nov. 2021, Heraklion, Greece.This paper proposes and validates a Interdomain Network Slicing framework for verticals, allowing them to directly participate in the establishment and control of end-to-end Communication Services deployment across multiple inter-operator domains. The framework progresses the means made available by different standards and research initiatives to enhance service requesting and provisioning interfaces for the stakeholders involved, namely operators and verticals. The framework is validated under two different use cases, showcasing effective end-to-end service instantiation and a first assessment towards dynamic service modification capability.This work has been supported by EC H2020 5GPPP 5Growth project (Grant 856709)
Vulnerability assessment of real water distribution networks using the TV-WPN informatics tool
The design, operation and rehabilitation of water supply systems must have an asset management strategy, addressing hydraulic, technical, economic, social, environmental, and health issues with a high level of complexity. The vulnerability assessment and the resilience increment of a water distribution networks can be supported by the emerging Theory of Vulnerability of Water Pipe Networks (TV-WPN), which allows to systematize failure scenarios and map the major disproportions between failure consequences and the initial damage. Failure scenarios are defined leading simultaneously with hydraulic capacity deterioration and structural integrity, the main issues of water networks safety.
The manual application of TV-WPN is almost impossible to be used in real-world water networks. So, it was initially tested using only simple theoretical networks, needing a new and more expeditious tool (like an automatic computation program) that could encourage its use by designers and managers of this type of hydraulic infrastructure. The recent development of the TV-WPN software tool allowed to speed up the calculation process, enabling the application of this theory to real water supply networks.
This work presents the application of tool to a real water distribution network located in a village of Braga municipality for analyze their hydraulic performance and vulnerability, as well as to check and evaluate TV-WPN performance in a real-world case. It was concluded that the frequent presence of pipelines with very low flow velocities (due to the imposition of regulatory minimum diameters) can compromise the successful application of this software to real water distribution networks, namely in rural areas where flow rates are generally lower. However it is also an opportunity for future developments
On the mobility of dialkyl adipates by PFGSE NMR, computer simulations and other property measurement methods
Encontro realizado em Alacalá de Henares (Madrid), de 22 a 25 de Setembro de 2014Dialkyl adipates are a class of esters materials used as components of lubricants and plasticizers.
Diffusion of plasticizers in polymers is a complex process that is difficult to study [1].
As a contribution to understand this phenomenon, the self-diffusion coefficients of five dialkyl adipates (dimethyl, diethyl, dipropyl, dibuthyl and bis(2-ethylhexyl)) were measured by the PFGSTE method in the temperature range 20 to 60ºC. It was shown that these compounds follow the Stokes-Einstein equation [2]. In effect, the self-diffusion coefficients change linearly with T.η-1(η is the viscosity). The dependence of the activation energies for self-diffusion is discussed in terms of size and branching of the alkyl chains of the adipates.
Molecular dynamics (MD) simulations were done for these sytems in order to predict the diffusion
coefficients as a function of temperature [3].
Acknolwedgements:
This work was supported by the Strategic Projects PEst-OE/QUI/UI0100/2011 and PEst-OE/QUI/
UI0100/2013, both funded by Fundação para a Ciência e a Tecnologia (FCT, Portugal). We thank also FCT
for funding the NMR facility through Project RECI/QEQ-QIN/0189/2012.
References:
[1] Rahman M.; Brazel C. S., Prog. Polym. Sci. 2004, 29, 1223–1248.
[2] Price W.S, NMR Studies of Translation Motion, Cambridge University Press, Cambridge, 2009.
[3] Pereira, L. A. M.; Martins, L. F. G.; Ascenso, J. R; Morgado, P.; Ramalho, J. P. P.; Filipe, E. J. M., J. Chem. Eng. Data 2014, accepted for publication
Solid-liquid phase equilibrium: in search of suitable PCMs for low temperature energy storage
Centro de Química Estrutural is a Research Unit funded by Fundação para a Ciência e Tecnologia through
projects UIDB/00100/2020 and UIDP/00100/2020.
• Institute of Molecular Sciences is an Associate Laboratory funded by FCT through project LA/P/0056/2020.
• M.C.M. Sequeira acknowledges the PhD grant funded by FCT ref. UI/BD/152239/2021.N/
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