Demand management for home energy networks using cost-optimal appliance scheduling

This paper uses problem decomposition to show that optimal dynamic home energy prices can be used to reduce the cost of supplying energy, while at the same time reducing the cost of energy for the home users. The paper makes no specific recommendations on the nature of energy pricing, but shows that energy prices can normally be found that not only result in optimal energy consumption schedules for the energy provider's problem and are economically viable for the energy provider, but also reduce total users energy costs. Following this, the paper presents a heuristic real-time algorithm for demand management using home appliance scheduling. The presented algorithm ensures users' privacy by requiring users to only communicate their aggregate energy consumption schedules to the energy provider at each iteration of the algorithm. The performance of the algorithm is evaluated using a comprehensive probabilistic user demand model which is based on real user data from energy provider E.ON. The simulation results show potential reduction of up to 17% of the mean peak-to-average power estimate, reducing the user daily energy cost for up to 14%

The Effects of Different Doses of Sildenafil on Coronary Blood Flow and Oxidative Stress in Isolated Rat Hearts

The dose-response relationship of sildenafil effects on cardiac function is not completely elucidated. The aim of this study was to assess the effects of different doses of sildenafil on coronary flow and oxidative stress in isolated rat hearts. Coronary flow and markers of oxidative stress, including nitrite outflow, and superoxide anion production in coronary effluent, were determined for isolated rat hearts. The experiments were performed during control conditions and in the presence of sildenafil (10, 20, 50, 200 nM) alone or with Nω-nitro-L-arginine monomethyl ester (L-NAME) (30 μM). Sildenafil was shown to result in a significant increase in coronary flow at lower coronary perfusion pressure (CPP) values at all administered doses, whereas, with an increase in CPP, a reduction in coronary flow was observed. An increase in nitric oxide (NO) was most pronounced in the group treated with the lowest dose of sildenafil at the highest CPP value. After the inhibition of the NO-cyclic guanosine monophosphate (cGMP) signaling (NOS) system by L-NAME, only a dose of 200 nM sildenafil was high enough to overcome the inhibition and to boost release of O2−. That effect was CPP-dependent, with statistical significance reached at 80, 100 and 120 mmHg. Our findings indicate that sildenafil causes changes in heart vasculature in a dose-dependent manner, with a shift from a vasodilatation effect to vasoconstriction with a pressure increase. The highest dose administered is capable of producing superoxide anion radicals in terms of NOS system inhibition

Impact of renal impairment on atrial fibrillation: ESC-EHRA EORP-AF Long-Term General Registry

Background: Atrial fibrillation (AF) and renal impairment share a bidirectional relationship with important pathophysiological interactions. We evaluated the impact of renal impairment in a contemporary cohort of patients with AF. Methods: We utilised the ESC-EHRA EORP-AF Long-Term General Registry. Outcomes were analysed according to renal function by CKD-EPI equation. The primary endpoint was a composite of thromboembolism, major bleeding, acute coronary syndrome and all-cause death. Secondary endpoints were each of these separately including ischaemic stroke, haemorrhagic event, intracranial haemorrhage, cardiovascular death and hospital admission. Results: A total of 9306 patients were included. The distribution of patients with no, mild, moderate and severe renal impairment at baseline were 16.9%, 49.3%, 30% and 3.8%, respectively. AF patients with impaired renal function were older, more likely to be females, had worse cardiac imaging parameters and multiple comorbidities. Among patients with an indication for anticoagulation, prescription of these agents was reduced in those with severe renal impairment, p <.001. Over 24 months, impaired renal function was associated with significantly greater incidence of the primary composite outcome and all secondary outcomes. Multivariable Cox regression analysis demonstrated an inverse relationship between eGFR and the primary outcome (HR 1.07 [95% CI, 1.01–1.14] per 10 ml/min/1.73 m2 decrease), that was most notable in patients with eGFR <30 ml/min/1.73 m2 (HR 2.21 [95% CI, 1.23–3.99] compared to eGFR ≥90 ml/min/1.73 m2). Conclusion: A significant proportion of patients with AF suffer from concomitant renal impairment which impacts their overall management. Furthermore, renal impairment is an independent predictor of major adverse events including thromboembolism, major bleeding, acute coronary syndrome and all-cause death in patients with AF

Ultra-thin mems fabricated tynodes for electron multiplication

For decades, photomultiplier tubes (PMTs) have been the most common choice in single photon detection, covering the spectral range from deep-ultraviolet to nearinfrared. PMT is a vacuum tube with three crucial components: photocathode, chain of dynodes and anode. At the photocathode, photons are converted to electrons in a photoelectric effect, after which they are directed to the dynodes chain. The material and geometry of dynodes are chosen to efficiently amplify the charge through the secondary electron emission (in reflection mode). Finally, created avalanche of electrons is collected and measured by the anode. Timed Photon Counter (TiPC) is a novel vacuum-based photomultiplier proposed to overcome limitations of PMTs in terms of size, speed, spatial resolution and operation in the presence of magnetic field. The key novelty of TiPC is a tynode – a large-size array of ultra-thin, free-standing membranes which, in contrast to dynodes, multiply electrons in the transmission mode. Due to the short and straight crossing paths of electrons between subsequent tynodes, the time resolution of the TiPC can be in the order of 10 -12 s. The set of tynodes is placed under the photocathode, and on top of a CMOS detecting chip. With such design, TiPC represents a light, compact and ultra-fast photodetecting device with a high relevance for solid state, atomic and molecular physics experiments, medical imaging and 3D optical imaging. The focus of this thesis is microelectromechanical systems (MEMS) fabrication of the tynodes. To our knowledge, this is the first time MEMS technology is employed as a powerful tool for the production of large arrays of free-standing membranes, with thicknesses of only a few nanometers, to be used in photodetection. Detailed analysis in terms of mechanical, optical, electrical and structural properties were performed in order to discern the most suitable material for the TiPC application among the investigated candidates. The transmission SEY (TSEY) of the released tynodes is analysed with a dedicated setup, specifically developed in our group, inserted in a scanning electron microscope (SEM). Low pressure chemical vapour deposition (LPCVD) was employed as a technique to grow silicon nitride (SiN) tynodes with varied layout, elemental stoichiometry and thicknesses in the range from 25 to 40 nm. Due to its inability to produce good-quality films with thicknesses lower than 20 nm, LPCVD was replaced by atomic layer deposition (ALD). It was found that SiN performs poorly in terms of secondary electron emission (SEE), and we selected Al2O3 (alumina) as the next tynode material. The ALD of alumina is investigated in the temperature range from 300 down to 100 °C, with the goal to determine its viability in the coating of temperature-sensitive substrates such as photoresist. We demonstrated the fabrication of 5 – 25 nm-thick ALD alumina tynodes which exhibited moderately high TSEY. Apart from SiN and alumina, other materials subjected to SEE analysis in this work were: chemical vapour deposited (CVD) ultrananocrystalline diamond (UNCD), monocrystalline silicon and LPCVD silicon carbide (SiC). Applying atomic layer deposited magnesium oxide (MgO) as the tynode material resulted in a transmission secondary electron yield (TSEY) of up to 5.5, by which it proved to be the most efficient electron multiplier among materials taken into account in this work. During the fabrication of tynodes, SEE films were exposed to different MEMS processing steps, and thus inevitably undewent a surface modification which alters the SEE properties. On that account, we conducted a study on the ALD MgO films subjected to various chemical and thermal treatments and explored the methods to further enhance their SEE. For the final application in the TiPC, stacked tynodes should provide the focusing of electrons. To meet this requirement, the emission film was grown on a pre-patterned substrate, which enabled hemi-spherical shape of the released membranes. Finally, for the vertical stacking and alignment of the tynodes, steps for the formation of V-grooves were added in the standard fabrication flowchart.EKL Processin

Dealing with uncertainty in calibration of a stormwater biofilter model

Uncertainty is a part of every modelling process and is caused by many different sources. Therefore, good and reliable model predictions are often very hard to obtain. Stormwater biofilter models are no exception. For a modeler to reduce uncertainty, first it is necessary to map and understand all the sources of uncertainty and their impact on the modelling processes. This paper is focused on understanding and reduction of uncertainties during calibration process of a model for prediction of treatment efficiency of stormwater biofilters (bioretentions and raingardens). The model was applied to Monash Car Park Biofilter, to simulate removal of atrazine for which removal performance data have been available over 6 simulated storm tests. The model was first calibrated, and then sensitivity analysis has been carried out for the most sensitive model parameters. The results show the key sources of uncertainties and links between them. The predictive uncertainty intervals were constructed, suggesting that the developed model is sound