424 research outputs found
Distribution power loss minimization via optimal sizing and placement of shunt capacitor and distributed generator with network reconfiguration
The population is speeding up and the demands for electrical energy are clearly increasing, this growth in load leads to higher power loss and Voltage drop. This paper is focused on a method to decrease the power losses and voltage profile improvement. The first suggested technique binary particle swarm optimization BPSO is utilized for solving the problem of the power loss minimization in network distribution. This work based on optimum position and sizing of the distribution generation (DG) units, shunt capacitor (SC) with network reconfiguration is applied to show the improvement of the network distribution efficiency. The MATLAB programming part and software package MATPOWER7 are used to simulate 69-bus and 33-bus test system with three different cases of loads and different number of DG and SC. The result showed a positive impact on system efficiency in comparison with other previous studies. This paper showed that increase of DG and capacitor does not usually give the best result although the increase of system cost, maintenance, and the units' distance for gas supplying
Postgraduate pedagogy in pandemic times: Online forums as facilitators of access to dialogic interaction and scholarly voices
In 2020, when the switch to remote teaching and learning required redesigning asynchronous on-line versions of face-to-face courses, we were concerned about whether access to engaged and dialogic learning could be facilitated in this new space. In attempting to address this concern we asked students in a B Ed Honours course to post, in an online forum, their reflective responses to weekly readings and to each other’s posts. This discussion forum became the engine of the course. With their permission, the posts of students in the 2021 cohort, together with their summative reflective reading response assignment, were analysed in order to understand different kinds of dialogic interactions and their affordances for reducing the potential alienation of asynchronous learning. One of the key findings that emerged from this analysis is the role of dialogic interaction in facilitating the development of personal, professional and scholarly voices which contributed to epistemic access. Our analysis was informed by the theoretical work of Bakhtin on the dialogic and by theoretical and empirical work of scholars in the field of critical pedagogies. We use examples from the writing of a ‘stronger’ and a ‘weaker’ student to illustrate how students negotiated roles and positions for themselves by appropriating and using the textual resources available on the forum. We argue for the value of sustained practice in ‘writing about reading’, of reading each other’s writing and of ‘writing back’ to one another on-line, for the gradual acquisition of a range of confident voices and for enhanced understanding of module content
Optimum Wideband High Gain Analog Beamforming Network for 5G Applications
A broadband high-gain millimeter-wave (mmWave) array beamforming network (BFN) design, analysis, and implementation based on the Rotman lens antenna array feeding are presented. The BFN is intended for operation in the (26-40) GHz frequency band for a wide range of potential applications in the fifth generation (5G). The system is made on Rogers substrate, RO6010, to provide compatibility with standard planar low-cost processing techniques for millimeter-wave monolithic integrated circuit (MMIC). The measured results show the system capability of 80° beam scanning for different angles at -39.7°, -26.5°, -13.3°, 0°, +13.3°, +26.5°, and +39.5° at 28 GHz. With these features in addition to being compact size, low profile, and lightweight, this BFN is suitable for various millimeter-wave and 5G applications such as the advanced multi-in multi-out (MIMO) systems, remote sensing, and automotive radar
Reevaluation Body Weight and Age with Standardized Uptake Value in the Liver Cancer for [18F] FDG PET/CT
Standardized uptake values, often known as SUVs, are frequently utilized in the process of measuring 18F-fluorodeoxyglucose (FDG) uptake in malignancies . In this work, we investigated the relationships between a wide range of parameters and the standardized uptake values (SUV) found in the liver. Examinations with 18F-FDG PET/CT were performed on a total of 59 patients who were suffering from liver cancer. We determined the SUV in the liver of patients who had a normal BMI (between 18.5 and 24.9) and a high BMI (above 30) obese. After adjusting each SUV based on the results of the body mass index (BMI) and body surface area (BSA) calculations, which were determined for each patient based on their height and weight. Under a variety of different circumstances, SUVs were evaluated based on their means and standard deviations. Scatterplots were created to illustrate the various weight and SUV variances. In addition to that, the SUVs that are appropriate for each age group were determined. SUVmax in the liver was statistical significantly in obese BMI and higher BSA, p- value <0.001). Age appeared to be the most important predictor of SUVmax and was significantly associated with the liver SUVmax with mean value (58.93±13.57). Conclusions: Age is a factor that contributes to variations in the SUVs of the liver. These age-related disparities in SUV have been elucidated as a result of our findings, which may help clinicians in doing more accurate assessments of malignancies. However, the SUV overestimates the metabolic activity of each and every individual, and this overestimation is far more severe in people who are obese compared to people who have a body mass index that is normal (BMI).
Insights into improved ferroelectric and electrocaloric performance of Ba0.85Ca0.15Ti0.9Zr0.1O3 thick films grown by the electrophoretic deposition
Lead-free Ba0.85Ca0.15Ti0.9Zr0.1O3 (BCZT) bulk ceramics have recently gained attention as one of the attractive
candidates for electrocaloric cooling due to their large heat absorption capacity induced by electro-structural
phase transition near room temperature. However, adiabatic temperature change (ΔT) at room temperature in
ceramics has been limited by their relatively low dielectric breakdown strength. Thick films, in this respect,
possess the advantages of ceramics (volume) and thin films (thickness). In this work, a systematic ferroelectric
and electrocaloric investigation of BCZT thick films, fabricated by electrophoretic deposition combined with
laser annealing, has been carried out. Laser annealing at an optimized energy density of 398 W/cm2 has resulted
in densely packed grain morphology with no compositional heterogeneities. Analysis of the scaling behavior of
dynamic hysteresis revealed that ferroelectric domain reversal in BCZT/Pt has good stability and low energy
consumption in the saturation region. The present thick films exhibited larger breakdown strength of 294 kV/cm
and recoverable energy storage density of ~7.3 J/cm3
, at least five-fold enhancement compared to the bulk
which is stable up to a 4 mm bending radius. The indirect electrocaloric measurements displayed parameters
such as a ΔT and entropy change (ΔS) of 2.94 K and 3.1 J kg− 1 K− 1 respectively, for 205 kV/cm which are more
than two orders increased compared to the bulk. Higher values of ΔT (1.9 K) at 25 ◦C, refrigerant capacity of 249
J/kg, and responsivity of 0.143 K mm/kV for BCZT/Pt film compared to relevant lead-free ferroelectric thick
films elucidate the potential use of these films for solid-state refrigeration applications. The work also presents
electrophoretic deposition with laser annealing as an alternative technique to widely studied tape-casting of thick
films for electrocaloric studies.publishe
Modulation of neuro-dopamine homeostasis in juvenile female Atlantic cod (Gadus morhua) exposed to polycyclic aromatic hydrocarbons and perfluoroalkyl substances
The dopaminergic effect of PAH and PFAS mixtures, prepared according to environmentally relevant concentrations, has been studied in juvenile female Atlantic cod (Gadus morhua). Benzo[a]pyrene, dibenzothiophene, fluorene, naphthalene, phenanthrene, and pyrene were used to prepare a PAH mixture, while PFNA, PFOA, PFOS, and PFTrA were used to prepare a PFAS mixture. Cod were injected intraperitoneally twice, with either a low (1×) or high (20×) dose of each compound mixture or their combinations. After 2 weeks of exposure, levels of plasma 17β-estradiol (E2) were significantly elevated in high PAH/high PFAS treated group. Brain dopamine/metabolite ratios (DOPAC/dopamine and HVA+DOPAC/dopamine) changed with E2 plasma levels, except for high PAH/low PFAS and low PAH/high PFAS treated groups. On the transcript levels, th mRNA inversely correlated with dopamine/metabolite ratios and gnrh2 mRNA levels. Respective decreases and increases of drd1 and drd2a after exposure to the high PAH dose were observed. Specifically, high PFAS exposure decreased both drds, leading to high plasma E2 concentrations. Other studied end points suggest that these compounds, at different doses and combinations, have different toxicity threshold and modes of action. These effects indicate potential alterations in the feedback signaling processes within the dopaminergic pathway by these contaminant mixtures.acceptedVersio
Video face replacement
We present a method for replacing facial performances in video. Our approach accounts for differences in identity, visual appearance, speech, and timing between source and target videos. Unlike prior work, it does not require substantial manual operation or complex acquisition hardware, only single-camera video. We use a 3D multilinear model to track the facial performance in both videos. Using the corresponding 3D geometry, we warp the source to the target face and retime the source to match the target performance. We then compute an optimal seam through the video volume that maintains temporal consistency in the final composite. We showcase the use of our method on a variety of examples and present the result of a user study that suggests our results are difficult to distinguish from real video footage.National Science Foundation (U.S.) (Grant PHY-0835713)National Science Foundation (U.S.) (Grant DMS-0739255
Recognising facial expressions in video sequences
We introduce a system that processes a sequence of images of a front-facing human face and recognises a set of facial expressions. We use an efficient appearance-based face tracker to locate the face in the image sequence and estimate the deformation of its non-rigid components. The tracker works in real-time. It is robust to strong illumination changes and factors out changes in appearance caused by illumination from changes due to face deformation. We adopt a model-based approach for facial expression recognition. In our model, an image of a face is represented by a point in a deformation space. The variability of the classes of images associated to facial expressions are represented by a set of samples which model a low-dimensional manifold in the space of deformations. We introduce a probabilistic procedure based on a nearest-neighbour approach to combine the information provided by the incoming image sequence with the prior information stored in the expression manifold in order to compute a posterior probability associated to a facial expression. In the experiments conducted we show that this system is able to work in an unconstrained environment with strong changes in illumination and face location. It achieves an 89\% recognition rate in a set of 333 sequences from the Cohn-Kanade data base
Does COVID-19 contribute to development of neurological disease?
Background: Although coronavirus disease 2019 (COVID-19) has been associated primarily with pneumonia, recent data show that the causative agent of COVID-19, the coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), can infect a large number of vital organs beyond the lungs, such as the heart, kidneys, and the brain. Thus, there is evidence showing possible retrograde transmission of the virus from the olfactory epithelium to regions of the brain stem. Methods: This is a literature review article. The research design method is an evidence-based rapid review. The present discourse aim is first to scrutinize and assess the available literature on COVID-19 repercussion on the central nervous system (CNS). Standard literature and database searches were implemented, gathered relevant material, and extracted information was then assessed. Results: The angiotensin-converting enzyme 2 (ACE2) receptors being the receptor for the virus, the threat to the central nervous system is expected. Neurons and glial cells express ACE2 receptors in the CNS, and recent studies suggest that activated glial cells contribute to neuroinflammation and the devastating effects of SARS-CoV-2 infection on the CNS. The SARS-CoV-2-induced immune-mediated demyelinating disease, cerebrovascular damage, neurodegeneration, and depression are some of the neurological complications discussed here. Conclusion: This review correlates present clinical manifestations of COVID-19 patients with possible neurological consequences in the future, thus preparing healthcare providers for possible future consequences of COVID-19
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