The impact of temperature and coupling coefficient on 4X4 micro-ring switch operation

2014 ◽  
Author(s):  
Cem Bonfil ◽  
Tom Smy ◽  
Marc Verreault
Keyword(s):  
Coupling Coefficient ◽  
Switch Operation ◽  
The Impact

scholarly journals Performance of Inductive Coupled Power Transfer Versus the Coil Shape - Investigation using Finite Element Analysis

2018 ◽  
Vol 225 ◽  
pp. 01017 ◽  
Author(s):  
Mohd Fakhizan Romlie ◽  
Kevin Lau ◽  
Mohd Zaifulrizal Zainol ◽  
Mohd Faris Abdullah ◽  
Ramani Kannan
Keyword(s):  
Magnetic Flux ◽  
Flux Density ◽  
Coupling Coefficient ◽  
Mutual Inductance ◽  
Magnetic Flux Density ◽  
Power Transfer ◽  
Element Analysis ◽  
Spiral Coil ◽  
The Impact ◽  
Coil Shape

The objective of this paper is to investigate the impact of the spiral coil shape of inductive coupled power transfer on its performance. The coil shapes evaluated are: circular, square and pentagon spiral shapes. The coils are modelled in Ansoft Maxwell software. Simulations are carried out to determine the mutual inductance, coupling coefficient and magnetic flux density. The performance in term of magnetic flux density, mutual inductance and coupling coefficient of the three coils shapes are compared. Of the three shapes, the pentagon is shown to have the best performance in term of its mutual inductance, coupling coefficient and magnetic flux density.

Abstract 14902: The Impact of Bicuspid Pulmonary Valve in Aortic Position After Arterial Switch for Transposition of the Great Arteries onNeoaortic Root and Neoaortic Valve Function; Propensity Score Matched Analysis

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Bobae Jeon ◽  
Eun Seok Choi ◽  
Bo Sang Kwon ◽  
Tae-Jin Yun ◽  
Chun Soo Park
Keyword(s):  
Aortic Valve ◽  
Propensity Score ◽  
Pulmonary Valve ◽  
Arterial Switch Operation ◽  
Z Score ◽  
Arterial Switch ◽  
Switch Operation ◽  
Valve Function ◽  
The Impact

Objective: Neoaortic valve regurgitation which might be related to root dilatation is one of the major concerns following arterial switch operation (ASO) for transposition of the great arteries (TGA). This study investigated the effect of bicuspid neoaortic valve on neoaortic root morphology, function, and the long-term clinical outcomes after ASO for TGA using propensity score matching (PSM). Methods: From 1997 to 2018, 442 patients underwent ASO for TGA. Patients who underwent staged repair (n=15), were repaired at extremely old age (> 1 year, n=9), and died before discharge (n=46), and were lack of echocardiographic data at discharge (n=20) were excluded. Among a total of 352 eligible patients, 18 patients (5.1%) had a BPV. After PSM (1:4), 15 patients with BPV and 60 corresponding patients with tricuspid pulmonary valve were enrolled for analysis. Results: Baseline characteristics in both groups were similar. The median duration of follow-up was 9.9 years (4 months ~ 22.3 years). There was one late death. Freedom from reoperation at 10 years was 93.3 ± 6.4 % in bicuspid group and 88.7 ± 4.4 % in tricuspid group ( p =0.84). Reoperation for aortic valve or aortic root was rarely required during follow-up. Indexed dimension (z-score) of neoaortic annulus was not increased in both groups ( p =0.57) (Figure 1A), although there was a little increasing tendency in z-score of neoaortic sinus without intergroup difference ( p =0.69) (Figure 1B). Deterioration in neoaortic valve function was more prominent in bicuspid group (common odds ratio; 1.40 in bicuspid group [ p <0.01], and 1.12 in tricuspid group [ p =0.03], p =0.03) (Figure 1C). Conclusions: Arterial switch operation could be a safe option in selected patients with TGA associated with BPV without increasing the risk of reoperation. Deterioration of aortic valve function was more prominent in bicuspid group, which suggests that the neoaortic valve function would be deteriorated mainly by valve itself not root pathology.

scholarly journals The Impact of Prematurity on Morbidity and Mortality in Newborns with Dextro-transposition of the Great Arteries

2021 ◽  
Author(s):  
Vinzenz Boos ◽  
Christoph Bührer ◽  
Mi-Young Cho ◽  
Joachim Photiadis ◽  
Felix Berger
Keyword(s):  
Mechanical Ventilation ◽  
Preterm Infants ◽  
Arterial Switch Operation ◽  
Adverse Outcomes ◽  
Morbidity And Mortality ◽  
Term Infants ◽  
Perioperative Morbidity ◽  
Arterial Switch ◽  
Switch Operation ◽  
The Impact

AbstractPrematurity is a risk factor for adverse outcomes after arterial switch operation in newborns with d-TGA (d-TGA). In this study, we sought to investigate the impact of prematurity on postnatal and perioperative clinical management, morbidity, and mortality during hospitalization in neonates with simple and complex d-TGA who received arterial switch operation (ASO). Monocentric retrospective analysis of 100 newborns with d-TGA. Thirteen infants (13.0%) were born premature. Preterm infants required significantly more frequent mechanical ventilation in the delivery room (69.2% vs. 34.5%, p = 0.030) and during the preoperative course (76.9% vs. 37.9%, p = 0.014). Need for inotropic support (30.8% vs. 8.0%, p = 0.035) and red blood cell transfusions (46.2% vs. 10.3%, p = 0.004) was likewise increased. Preoperative mortality (23.1% vs 0.0%, p = 0.002) was significantly increased in preterm infants, with necrotizing enterocolitis as cause of death in two of three infants. In contrast, mortality during and after surgery did not differ significantly between the two groups. Cardiopulmonary bypass times were similar in both groups (median 275 vs. 263 min, p = 0.322). After ASO, arterial lactate (34.5 vs. 21.5 mg/dL, p = 0.007), duration of mechanical ventilation (median 175 vs. 106 h, p = 0.038), and venous thrombosis (40.0% vs. 4.7%, p = 0.004) were increased in preterm, as compared to term infants. Gestational age (adjusted unit odds ratio 0.383, 95% confidence interval 0.179–0.821, p = 0.014) was independently associated with mortality. Prematurity is associated with increased perioperative morbidity and increased preoperative mortality in d-TGA patients.

scholarly journals Switch operation safety

2019 ◽  
Vol 138 ◽  
pp. 01017 ◽  
Author(s):  
Boris Gluzberg ◽  
Vadim Korolev ◽  
Alexey Loktev ◽  
Irina Shishkina ◽  
Mikhail Berezovsky
Keyword(s):  
Relative Position ◽  
Rolling Stock ◽  
Total Probability ◽  
Conditional Probabilities ◽  
Dynamic Effects ◽  
Impact Effect ◽  
Bayes Formula ◽  
Switch Operation ◽  
The Cross ◽  
The Impact

The article studied the safety of passing the rolling stock by railway switches. On railway switches, counter rails provide the safe passage of the rolling stock by the wheelsets through the harmful space of the cross. The levels of dynamic effects arising from the passage of carriages by the railway switch significantly depend on the relative position of the wheelsets and elements of the switch, which is determined by the combination of their main geometric dimensions. To calculate the most unfavorable combinations of wheelset and gauge dimensions, taking into account the tolerances adopted for these dimensions, the method of probability compositions is used, based on the application of the theory of probability. The calculating apparatus of the approach using conditional probabilities of events based on the formulas of total probability and Bayes formula. The level of impact of the wheels on the counter-rail is regulated by rationing the values of the “impact effect” on the bent and catching parts of the counter-rail.

scholarly journals Intramural coronary pattern in patients with transposition: incidence and impact on follow-up

2020 ◽  
Vol 58 (1) ◽  
pp. 145-152
Author(s):  
Maciej Moll ◽  
Jadwiga A Moll ◽  
Jacek J Moll ◽  
Monika Łubisz ◽  
Krzysztof W Michalak
Keyword(s):  
Arterial Switch Operation ◽  
Surgical Techniques ◽  
Early Mortality ◽  
Rank Test ◽  
Coronary Anomalies ◽  
Arterial Switch ◽  
Switch Operation ◽  
The Impact ◽  
Intramural Coronary Artery ◽  
Overall Mortality

Abstract OBJECTIVES Coronary complications are still the main reason for early mortality after an arterial switch operation. The high incidence of coronary anomalies in patients with transposition of the great arteries may increase the difficulty of coronary transfer, and among them, an intramural pattern was shown to be an independent risk factor of early mortality. However, recently published studies have reported that this rare coronary variant has no impact on the survival rate. The aim of this study was to assess the frequency of intramural coronary patterns in patients with transposition and the impact on overall mortality after an arterial switch operation. Additionally, we presented all coronary arrangements associated with intramural patterns in our cohort and the surgical techniques used to manage them successfully. METHODS All arterial switch operations were retrospectively reviewed. In each case, the surgical reports contained detailed graphical representations and coronary anatomy patterns. All operatively confirmed intramural patterns were included in the analysis. RESULTS Among 806 patients, 271 patients had coronary anomalies (33.62%), and 28 patients had an intramural pattern (3.47%), which was frequently associated with other complex coronary anomalies (P &lt; 0.001). Overall survival was significantly higher in patients with intramural coronary artery patterns than in those with other coronary variants (21.34% vs 8.74%, P = 0.024, log-rank test). CONCLUSIONS Intramural patterns associated with transposition remain a surgical challenge and increase overall mortality in our cohort. To reliably confirm or reject the significance of the observed impact of this rare coronary variant, a multicentre data analysis is required.

Modelling a Disconnect Switch

2018 ◽  
Vol 19 (4) ◽  
Author(s):  
Pablo Mourente Miguel
Keyword(s):  
Circuit Breaker ◽  
Electric Arc ◽  
Voltage Variation ◽  
Capacitive Divider ◽  
Switch Operation ◽  
Voltage Change ◽  
Disconnect Switch ◽  
The Impact ◽  
Open Position ◽  
A Current

Abstract This article presents a model to simulate disconnecting switches in transient studies. The distance between contacts of a disconnecting switch does not change instantaneously; it takes several seconds to complete the full movement from closed to open, or vice-versa. The disconnecting switches are able to operate with lower current amplitudes, so a disconnecting switch is operated only when the circuit breaker is in open position. However, even with the circuit breaker open, there is a current flowing through the grading capacitors. The grading capacitors in conjunction with the busbar capacitance form a capacitive divider, and there is a floating voltage in the busbar. When the contacts of the disconnecting switch move, the withstand voltage varies and an electric arc appears. This arc is unstable and is interrupted and reignited several times. Each arc reignition causes a sudden voltage change that propagates through the busbar and impacts any connected equipment. The developed model, with the withstand voltage variation and the electric arc behaviour taken into account, calculates the fast transient overvoltages originated during a disconnecting switch operation. The amplitude and waveform of these overvoltages may then be used to evaluate the impact on insulation ageing.

Formation of Lunar Craters and Bright Rays as a Result of Meteorite Impacts

1962 ◽  
Vol 14 ◽  
pp. 415-418
Author(s):  
K. P. Stanyukovich ◽  
V. A. Bronshten
Keyword(s):  
Explosive Charge ◽  
The Moon ◽  
Meteorite Impacts ◽  
The Earth ◽  
Lunar Craters ◽  
The Impact

The phenomena accompanying the impact of large meteorites on the surface of the Moon or of the Earth can be examined on the basis of the theory of explosive phenomena if we assume that, instead of an exploding meteorite moving inside the rock, we have an explosive charge (equivalent in energy), situated at a certain distance under the surface.

The Geosciences Applied to Lunar Exploration

1962 ◽  
Vol 14 ◽  
pp. 169-257 ◽  
Author(s):  
J. Green
Keyword(s):  
Lunar Surface ◽  
Probable Mechanism ◽  
Point Of View ◽  
Lunar Exploration ◽  
Geological Model ◽  
Apply Geophysics ◽  
Surface Features ◽  
The Impact

The term geo-sciences has been used here to include the disciplines geology, geophysics and geochemistry. However, in order to apply geophysics and geochemistry effectively one must begin with a geological model. Therefore, the science of geology should be used as the basis for lunar exploration. From an astronomical point of view, a lunar terrain heavily impacted with meteors appears the more reasonable; although from a geological standpoint, volcanism seems the more probable mechanism. A surface liberally marked with volcanic features has been advocated by such geologists as Bülow, Dana, Suess, von Wolff, Shaler, Spurr, and Kuno. In this paper, both the impact and volcanic hypotheses are considered in the application of the geo-sciences to manned lunar exploration. However, more emphasis is placed on the volcanic, or more correctly the defluidization, hypothesis to account for lunar surface features.

Asteroid and Comet Impact Speeds upon Mars: Significance for Panspermia and the Supply of Organics

1997 ◽  
Vol 161 ◽  
pp. 197-201 ◽  
Author(s):  
Duncan Steel
Keyword(s):  
Probability Distributions ◽  
Regions Of Interest ◽  
Significant Fraction ◽  
Organic Chemicals ◽  
Impact Speed ◽  
The Mean ◽  
The Impact

AbstractWhilst lithopanspermia depends upon massive impacts occurring at a speed above some limit, the intact delivery of organic chemicals or other volatiles to a planet requires the impact speed to be below some other limit such that a significant fraction of that material escapes destruction. Thus the two opposite ends of the impact speed distributions are the regions of interest in the bioastronomical context, whereas much modelling work on impacts delivers, or makes use of, only the mean speed. Here the probability distributions of impact speeds upon Mars are calculated for (i) the orbital distribution of known asteroids; and (ii) the expected distribution of near-parabolic cometary orbits. It is found that cometary impacts are far more likely to eject rocks from Mars (over 99 percent of the cometary impacts are at speeds above 20 km/sec, but at most 5 percent of the asteroidal impacts); paradoxically, the objects impacting at speeds low enough to make organic/volatile survival possible (the asteroids) are those which are depleted in such species.

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