Global model SMF2 of the F2-layer maximum height

2015 ◽  
Vol 55 (5) ◽  
pp. 609-622 ◽  
Author(s):  
V. N. Shubin ◽  
A. T. Karpachev ◽  
V. A. Telegin ◽  
K. G. Tsybulya
Keyword(s):  
Global Model ◽  
Maximum Height ◽  
Layer Maximum

scholarly journals STATISTICS OF VARIATION RANGE OF F2- LAYER MAXIMUM HEIGHT OF THE IONOSPHERE

2019 ◽  
Vol 4 (326) ◽  
pp. 129-134
Author(s):  
Arthur Fedorovich Yakovets ◽  
◽  
Arezu Jahanshir ◽  
Galina Ivanovna Gordienko ◽  
Beybit Tenelovich Zhumabayev ◽  
...  
Keyword(s):  
Maximum Height ◽  
Layer Maximum ◽  
Variation Range

Surfing the Quantum World

2017 ◽  
Author(s):  
Frank S. Levin
Keyword(s):  
Quantum Mechanics ◽  
Quantum Theory ◽  
Musical Instrument ◽  
Popular Science ◽  
Quantum Spin ◽  
Exclusion Principle ◽  
Maximum Height ◽  
Core Concepts ◽  
The Many ◽  
The One

Surfing the Quantum World bridges the gap between in-depth textbooks and typical popular science books on quantum ideas and phenomena. Among its significant features is the description of a host of mind-bending phenomena, such as a quantum object being in two places at once or a certain minus sign being the most consequential in the universe. Much of its first part is historical, starting with the ancient Greeks and their concepts of light, and ending with the creation of quantum mechanics. The second part begins by applying quantum mechanics and its probability nature to a pedagogical system, the one-dimensional box, an analog of which is a musical-instrument string. This is followed by a gentle introduction to the fundamental principles of quantum theory, whose core concepts and symbolic representations are the foundation for most of the subsequent chapters. For instance, it is shown how quantum theory explains the properties of the hydrogen atom and, via quantum spin and Pauli’s Exclusion Principle, how it accounts for the structure of the periodic table. White dwarf and neutron stars are seen to be gigantic quantum objects, while the maximum height of mountains is shown to have a quantum basis. Among the many other topics considered are a variety of interference phenomena, those that display the wave properties of particles like electrons and photons, and even of large molecules. The book concludes with a wide-ranging discussion of interpretational and philosophic issues, introduced in Chapters 14 by entanglement and 15 by Schrödinger’s cat.

scholarly journals A Piezoelectric Wave-Energy Converter Equipped with a Geared-Linkage-Based Frequency Up-Conversion Mechanism

Sensors ◽  
2020 ◽  
Vol 21 (1) ◽  
pp. 204
Author(s):  
Shao-En Chen ◽  
Ray-Yeng Yang ◽  
Guang-Kai Wu ◽  
Chia-Che Wu
Keyword(s):  
Power Generation ◽  
Wave Energy ◽  
Wave Motion ◽  
Wave Energy Converter ◽  
Gear Train ◽  
Piezoelectric Composite ◽  
Maximum Height ◽  
Resistive Load ◽  
Linkage Mechanism ◽  
Energy Converter

In this paper, a piezoelectric wave-energy converter (PWEC), consisting of a buoy, a frequency up-conversion mechanism, and a piezoelectric power-generator component, is developed. The frequency up-conversion mechanism consists of a gear train and geared-linkage mechanism, which converted lower frequencies of wave motion into higher frequencies of mechanical motion. The slider had a six-period displacement compared to the wave motion and was used to excite the piezoelectric power-generation component. Therefore, the operating frequency of the piezoelectric power-generation component was six times the frequency of the wave motion. The developed, flexible piezoelectric composite films of the generator component were used to generate electrical voltage. The piezoelectric film was composed of a copper/nickel foil as the substrate, lead–zirconium–titanium (PZT) material as the piezoelectric layer, and silver material as an upper-electrode layer. The sol-gel process was used to fabricate the PZT layer. The developed PWEC was tested in the wave flume at the Tainan Hydraulics Laboratory, Taiwan (THL). The maximum height and the minimum period were set to 100 mm and 1 s, respectively. The maximum voltage of the measured value was 2.8 V. The root-mean-square (RMS) voltage was 824 mV, which was measured through connection to an external 495 kΩ resistive load. The average electric power was 1.37 μW.

Management of optic disc pit-associated maculopathy: A case series from a tertiary referral center

2021 ◽  
pp. 112067212110237
Author(s):  
Ilkay Kilic Muftuoglu ◽  
Ecem Onder Tokuc ◽  
V Levent Karabas
Keyword(s):  
Optic Disc ◽  
Case Series ◽  
Internal Limiting Membrane ◽  
Maximum Height ◽  
Optic Disc Pit ◽  
Tertiary Referral Center ◽  
Number Of Patients ◽  
The Mean ◽  
Foveal Center

Purpose: To report outcomes of pars plana vitrectomy (PPV) combined with internal limiting membrane (ILM) stuffing technique in patients with optic disc pit associated maculopathy (ODP-M). Methods: Data including best-corrected visual acuity (BCVA), central macular thickness (CMT), foveal center point thickness (FCP), and maximum height of fluid (max_fluid) (intraretinal or subretinal) were collected from the medical records of the patients. Results: Six eyes of six patients with a mean age of 28.0 ± 17.68 years (range: 9–53 year) underwent PPV + ILM plug surgery. The mean follow-up duration was 25.62 ± 26.11 months (range: 11.80–78.00 month) duration. The mean BCVA increased from 1.25 ± 1.04 logMAR (20/355, Snellen equivalent) to 0.86 ± 1.09 logMAR (20/144, Snellen equivalent) at last follow-up ( p = 0.043). Compared to baseline, CMT, FCP, and max_fluid significantly decreased at all visits after the surgery ( p < 0.05 for all visits). At last follow-up, 66.6% of the eyes (four eyes) showed complete resolution of fluid at a mean of 5.25 ± 4.99 months (range: 1–12 months) after the surgery. Conclusion: PPV with ILM plug seemed to be an effective surgical technique in ODP-M. Studies with longer follow-up and higher number of patients are needed to confirm our results.

scholarly journals FedPSO: Federated Learning Using Particle Swarm Optimization to Reduce Communication Costs

Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 600
Author(s):  
Sunghwan Park ◽  
Yeryoung Suh ◽  
Jaewoo Lee
Keyword(s):  
Particle Swarm Optimization ◽  
Data Privacy ◽  
Particle Swarm ◽  
Global Model ◽  
Network Communication ◽  
Improve Performance ◽  
Communication Performance ◽  
Swarm Optimization ◽  
Model Update ◽  
Network Environments

Federated learning is a learning method that collects only learned models on a server to ensure data privacy. This method does not collect data on the server but instead proceeds with data directly from distributed clients. Because federated learning clients often have limited communication bandwidth, communication between servers and clients should be optimized to improve performance. Federated learning clients often use Wi-Fi and have to communicate in unstable network environments. However, as existing federated learning aggregation algorithms transmit and receive a large amount of weights, accuracy is significantly reduced in unstable network environments. In this study, we propose the algorithm using particle swarm optimization algorithm instead of FedAvg, which updates the global model by collecting weights of learned models that were mainly used in federated learning. The algorithm is named as federated particle swarm optimization (FedPSO), and we increase its robustness in unstable network environments by transmitting score values rather than large weights. Thus, we propose a FedPSO, a global model update algorithm with improved network communication performance, by changing the form of the data that clients transmit to servers. This study showed that applying FedPSO significantly reduced the amount of data used in network communication and improved the accuracy of the global model by an average of 9.47%. Moreover, it showed an improvement in loss of accuracy by approximately 4% in experiments on an unstable network.

scholarly journals Morphological variables associated with ruptured basilar tip aneurysms

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jian Zhang ◽  
Anil Can ◽  
Pui Man Rosalind Lai ◽  
Srinivasan Mukundan ◽  
Victor M. Castro ◽  
...  
Keyword(s):  
Statistical Significance ◽  
Multivariable Analysis ◽  
Aneurysm Rupture ◽  
Size Ratio ◽  
Width Ratio ◽  
Maximum Height ◽  
Morphological Parameters ◽  
Flow Angle ◽  
Aneurysm Wall ◽  
Fisher Grade

AbstractMorphological factors of intracranial aneurysms and the surrounding vasculature could affect aneurysm rupture risk in a location specific manner. Our goal was to identify image-based morphological parameters that correlated with ruptured basilar tip aneurysms. Three-dimensional morphological parameters obtained from CT-angiography (CTA) or digital subtraction angiography (DSA) from 200 patients with basilar tip aneurysms diagnosed at the Brigham and Women’s Hospital and Massachusetts General Hospital between 1990 and 2016 were evaluated. We examined aneurysm wall irregularity, the presence of daughter domes, hypoplastic, aplastic or fetal PCoAs, vertebral dominance, maximum height, perpendicular height, width, neck diameter, aspect and size ratio, height/width ratio, and diameters and angles of surrounding parent and daughter vessels. Univariable and multivariable statistical analyses were performed to determine statistical significance. In multivariable analysis, presence of a daughter dome, aspect ratio, and larger flow angle were significantly associated with rupture status. We also introduced two new variables, diameter size ratio and parent-daughter angle ratio, which were both significantly inversely associated with ruptured basilar tip aneurysms. Notably, multivariable analyses also showed that larger diameter size ratio was associated with higher Hunt-Hess score while smaller flow angle was associated with higher Fisher grade. These easily measurable parameters, including a new parameter that is unlikely to be affected by the formation of the aneurysm, could aid in screening strategies in high-risk patients with basilar tip aneurysms. One should note, however, that the changes in parameters related to aneurysm morphology may be secondary to aneurysm rupture rather than causal.

Sign in / Sign up

Export Citation Format

Share Document