Real-Time Simulation of small-scale power grids with software in-the-loop and hardware in-the-loop experiments

As the term “Smart Grid” defines, the electricity supply network uses smart devices to monitor the state quantities, and digital communication technologies to support fast decisions and control. This work is focused on developing a flexible IoT architecture to support real-time tests and to validate some algorithms for monitoring and maintenance of micro-systems as intelligent smart functions on the virtual model of a small-scale power grid, through Real-Time Simulation Software in-the-loop (SIL) and Hardware in-the-loop (HIL). We aim to explain the implementation aspects of a microgrid in MATLAB/Simulink, based on real grid data and “smart customers” as end-users (capable of exchanging data with the outside of the simulation environment), then compiled in Real-Time environment (RT-LAB software). The overall communication infrastructure relies on different protocols for the data exchange between grid and application components (TCP and MQTT protocol). Furthermore, the presence of an MQTT broker makes the architecture flexible, since it allows the integration of different services

Magnetic nulls and super-radial expansion in the solar corona

Magnetic fields in the sun's outer atmosphere -- the corona -- control both solar-wind acceleration and the dynamics of solar eruptions. We present the first clear observational evidence of coronal magnetic nulls in off-limb linearly polarized observations of pseudostreamers, taken by the Coronal Multichannel Polarimeter (CoMP) telescope. These nulls represent regions where magnetic reconnection is likely to act as a catalyst for solar activity. CoMP linear-polarization observations also provide an independent, coronal proxy for magnetic expansion into the solar wind, a quantity often used to parameterize and predict the solar wind speed at Earth. We introduce a new method for explicitly calculating expansion factors from CoMP coronal linear-polarization observations, which does not require photospheric extrapolations. We conclude that linearly-polarized light is a powerful new diagnostic of critical coronal magnetic topologies and the expanding magnetic flux tubes that channel the solar wind

A theoretical study of the tautomerism and vibrational spectra of 4,5-diamine-2,6-dimercaptopyrimidine

The 4,5-diamine-2,6-dimercaptopyrimidine (DADMcP) compound is an interesting multifunctional species exhibiting a rather complex tautomerism, encompassing nine tautomeric forms. Investigation of tautomerism in this compound has been carried out by means of FTIR spectroscopy, in association with ab-initio HF/SCF and DFT calculations. According to this study three tautomers are energetically favored; the thione form being the most stable one. The theoretical vibrational spectra of such tautomeric forms have been successfully simulated by means of DFT calculations, allowing the elucidation and assignment of the complex composition of the vibrational bands observed for the mixture of isomers.A 4,5-diamina-2,6-dimercaptopirimidina (DADMcP) constitui uma molécula multifuncional que apresenta uma tautomeria bastante complexa, com nove formas isoméricas possíveis. O estudo da tautomeria nesse composto foi realizado por meio da espectroscopia FTIR em associação com cálculos ab-initio HF/SCF e DFT. De acordo com os resultados teóricos, três tautômeros são favorecidos energeticamente, sendo a tiona a forma a mais estável. Os espectros vibracionais das formas tautoméricas mais estáveis foram simulados através de cálculos de DFT, permitindo a atribuição e elucidação do quadro complexo de bandas vibracionais observado experimentalmente, envolvendo a mistura de isômeros

A novel metric for coronal MHD models

[1] In the interest of quantitatively assessing the capabilities of coronal MHD models, we have developed a metric that compares the structures of the white light corona observed with SOHO LASCO C2 to model predictions. The MAS model is compared to C2 observations from two Carrington rotations during solar cycle 23, CR1913 and CR1984, which were near the minimum and maximum of solar activity, respectively, for three radial heights, 2.5 R⊙, 3.0 R⊙, and 4.5 R⊙. In addition to simulated polarization brightness images, we create a synthetic image based on the field topology along the line of sight in the model. This open-closed brightness is also compared to LASCO C2 after renormalization. In general, the model\u27s magnetic structure is a closer match to observed coronal structures than the model\u27s density structure. This is expected from the simplified energy equations used in current global corona MHD models

Open and / or laparoscopic surgical treatment of liver hydatic cysts

Hydatid disease is a severe parasitic disease with a widely ranging distribution. In the human being the liver is the most frequent organ affected. 1 The treatment should be individualized to the morphology, size, number and location of the cysts, that is why a variety of surgical operations have been advocated from complete resection like total pericystectomy or partial hepatectomy to laparoscopy to a minimally invasive procedures like percutaneous aspiration of cysts to conservative drug therapy. 3-4 This study compares laparoscopic versus open management of the hydatid cyst of liver the surgical approach to liver echinococcosis is still a controversial issue and shows our results of surgical treatment of liver hydatid cysts during a 3-years period

On the virtual inertia provision by BESS in low inertia power systems

This paper emphasizes the importance of battery energy storage systems (BESS) for frequency stability in low inertia power systems. A mixed input signal is considered for the BESS control, consisting of the frequency variation and the rate of change of frequency, as a solution to deploy the BESS for providing both inertia and primary frequency control. A sensitivity analysis on the influence of each input signal and the reaction time of the BESS on the frequency control, as well as on the frequency stabilization was performed. Simulation are conducted on a two-area interconnected power system to study and validate the capability of BESS to provide virtual inertia and contribute to system frequency regulatio

Analysis of videofluoroscopic variables affecting swallowing safety and efficiency in ophl patients

Open partial horizontal laryngectomy (OPHL) could represent a valuable alternative to total laryngectomy for selected laryngeal carcinoma. In long-term, occasional aspiration ranges from 12.9 to 67% after OPHL [1]. Rate of aspiration pneumonia can reach the 21.7% [2]. Main causes of swallowing impairment vary from a defective glottic closure to a reduced upper esophageal sphincter (UES) opening. At the present time, only one study analysed spatial and temporal videofluoroscopic variables to evaluate factors affecting postoperative aspiration. No studies before have compared videofluoroscopic variables between OPHL patients with and without dysphagia

The Whole Heliosphere Interval in the Context of a Long and Structured Solar Minimum: An Overview from Sun to Earth

Throughout months of extremely low solar activity during the recent extended solar-cycle minimum, structural evolution continued to be observed from the Sun through the solar wind and to the Earth. In 2008, the presence of long-lived and large low-latitude coronal holes meant that geospace was periodically impacted by high-speed streams, even though solar irradiance, activity, and interplanetary magnetic fields had reached levels as low as, or lower than, observed in past minima. This time period, which includes the first Whole Heliosphere Interval (WHI 1: Carrington Rotation (CR) 2068), illustrates the effects of fast solar-wind streams on the Earth in an otherwise quiet heliosphere. By the end of 2008, sunspots and solar irradiance had reached their lowest levels for this minimum (e.g., WHI 2: CR 2078), and continued solar magnetic-flux evolution had led to a flattening of the heliospheric current sheet and the decay of the low-latitude coronal holes and associated Earth-intersecting high-speed solar-wind streams. As the new solar cycle slowly began, solar-wind and geospace observables stayed low or continued to decline, reaching very low levels by June – July 2009. At this point (e.g., WHI 3: CR 2085) the Sun–Earth system, taken as a whole, was at its quietest. In this article we present an overview of observations that span the period 2008 – 2009, with highlighted discussion of CRs 2068, 2078, and 2085. We show side-by-side observables from the Sun’s interior through its surface and atmosphere, through the solar wind and heliosphere and to the Earth’s space environment and upper atmosphere, and reference detailed studies of these various regimes within this topical issue and elsewhere

Microstructure and photocatalytic activity of APS coatings obtained from different TiO2 nanopowders

In recent years, intense research has shown that thermal spray techniques, especially atmospheric plasma spraying (APS), can be used to obtain nanostructured TiO2 coatings with effective photocatalytic activity. This study compares the photocatalytic activity of APS coatings obtained from different powders: two nanostructured TiO2 powders produced by spray-drying of two TiO2 nanosuspensions with different solids contents, one spray-dried powder obtained from a suspension comprising a mixture of submicronic and nanometric TiO2 particles and finally one commercial, nanostructured, TiO2 spray-dried powder. All powders were characterised by XRD, FEG-ESEM, granule size distribution, and a flowability evaluation. Feedstock powders were then deposited on austenitic stainless steel coupons using APS. Hydrogen or helium was used as secondary plasma gas. Coating microstructure and phase composition were characterised using FEG-ESEM and XRD techniques; coating anatase content was quantified by the Rietveld method. A significant amount of anatase to rutile transformation was found to take place during the plasma spraying process. In general, the coatings had a bimodal microstructure characterised by the presence of completely fused areas in addition to non-molten areas consisting of agglomerates of anatase nanoparticles. Results also showed that anatase content and porosity of the coatings largely depend on the secondary plasma gas nature, as well as on the characteristics of the feedstock. Finally the photocatalytic activity of the coatings was determined by measuring the degradation of methylene blue dye in an aqueous solution. A reasonably good fit of a first-order kinetic model to the experimental data was found for all coatings. The values of the kinetic constant were related to feedstock characteristics as well as to plasma spraying conditions. (C) 2012 Elsevier B.V. All rights reserved.Bordes, MC.; Vicent, M.; Moreno, A.; Moreno, R.; Borrell Tomás, MA.; Salvador Moya, MD.; Sanchez, E. (2013). Microstructure and photocatalytic activity of APS coatings obtained from different TiO2 nanopowders. Surface and Coatings Technology. 220:179-186. doi:10.1016/j.surfcoat.2012.08.059S17918622

The effects of birth weight and gender on neonatal mortality in north central Nigeria

<p>Abstract</p> <p>Background</p> <p>Worldwide 15.5% of neonates are born with low birth weight, 95.6% of them in the developing countries. Prematurity accounts for 10% of neonatal mortality globally. The purpose of this study was to evaluate the effects of birth weight and gender on neonatal outcome.</p> <p>Findings</p> <p>The data of 278 neonates managed in the Special Care Baby Unit (SCBU) of Jos University Teaching Hospital (JUTH) over a 2 year period from July 2006 to June 2008 were analyzed.</p> <p>One hundred and fifty nine (57.2%) were males and 119(42.8%) females. There were 87(31.3%) preterm and 191 (68.7%) term babies. Twelve of the babies died. Seven (2.52%) and 5 (1.80%) being males and females respectively. The neonatal mortality rate by gender was not significant (p > 0.05). The neonatal mortality was 25.2 deaths per 1000 live births for boys and 18.0 for girls. The mean birth weights of the preterm and term babies were 1.88 ± 0.47 kg and 3.02 ± 0.50 kg respectively, with a mean gestational age of 30.62 ± 3.65 weeks and 38.29 ± 0.99 weeks respectively.</p> <p>Eighty seven (31.3%) of the babies were of low birth weight, 188(67.6%) were of normal birth weight and 3(1.1%) high birth weight. Of the low birth weight babies, 6(2.2%) were term small for gestational age. Six (2.2%) of the preterm infants had normal birth weight.</p> <p>Eleven of the babies that died were preterm low birth weight. The overall mortality rate was 4.32%. The birth weight specific mortality rate was 126 per 1000 for the preterm low birth weight and 5 per 1000 for the term babies. Birth weight unlike gender is a significant predictor of mortality, mortality being higher in neonates of <2.5 kg (OR = 0.04; 95% Cl 0.005-0.310, p = 0.002) (p = 0.453). Seven (58.3%) and 4(33.3%) of the pre-terms that died were appropriate and large for gestational age respectively. Gestational age is not a significant predictor of neonatal mortality (p = 0.595). Babies delivered at less than 37 weeks of gestation recorded a higher rate of mortality than those of 37 weeks and above (p = 0.000).</p> <p>The subjects showed one or more major clinical indications for admission. The major clinical indications for the preterm and term babies were respectively as follows: neonatal sepsis 63(22.7%) and 124(44.6%); neonatal jaundice 32(11.1%) and 71(24.7%); malaria 9(3.1%) and 13(4.5%); birth asphyxia 3(1.0%) and 7(2.4%). Neonatal sepsis was a common denominator among the babies that died.</p> <p>Conclusion</p> <p>Birth weight unlike gender is a significant predictor of neonatal outcome</p