An Alternative Explanation of the Orbital Expansion of Titan and Other Bodies in the Solar System

Recently it was found from Cassini data that the mean recession speed of Titan from Saturn is v = 11.3 ± 2.0 cm/yr which corresponds to a tidal quality factor of Saturn Q ≈ 100 while the standard estimate yields Q ≥ 6 · 104 . It was assumed that such a large speed v is due to a resonance locking mechanism of five inner mid-sized moons of Saturn. In this paper, we show that an essential part of v may come from a local Hubble expansion, where the Hubble-Lema&circ;ıtre constant H0 recalculated to the Saturn-Titan distance D is 8.15 cm/(yrD). Our hypothesis is based on many other observations showing a slight expansion of the Solar system and also of our Galaxy at a rate comparable with H0. We demonstrate that the large disproportion in estimating the Q factor can be just caused by the local expansion effect. [Accepted for publication in "Gravitation and Cosmology". The paper is to appear in Vol. 28, Issue 2 (2022) of the journal Gravitation and Cosmology.]

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Optimization of Scheduling Technique Rooted on Software Test Routines for Embedded Cores using Quality Factor

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.c8820.019320 ◽

2020 ◽

Vol 9 (3) ◽

pp. 2034-2038

Keyword(s):

Quality Factor ◽

Digital Circuits ◽

Research Work ◽

Software Test ◽

Q Factor ◽

Embedded Cores ◽

Testing Performance ◽

Self Test ◽

Scheduling Technique ◽

Additional Area

Most of the research work to test the fast processors is carried out using external devices as testers;but it was not technically & financially workable. To fulfill the required performance along with providing efficient functionality, an appropriate testingism must be employed by the digital circuits. The best way is to follow testing as an integral part that is self-test. Conventionally large amount of data was stored in an external tester.But there was a difficulty in at speed testing performance using these external hardware. Hence, Builtin-self-test was invented which verifies failure free nature of circuit under test (CUT) with a test mechanism as a part of system itself. It is observed that, if testing of any hardware is carried out with the help of built-in self test, it increases the requirement of additional area and indirectly responsible for forfeits due to degradation in performance.. If a powerful and power optimized core is to be designed, hardware BIST cannot be afforded due to these limitations. To overcome these disadvantages, a new software based BIST techniques is introduced which relies on software test patterns. Here this paper focuses on rooting of software test routines which works using optimization of scheduling and also a Q- factor is proposed to evaluate the nature of proposed method.

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A Geometrical Study on the Roof Tile-Shaped Modes in AlN-Based Piezoelectric Microcantilevers as Viscosity–Density Sensors

Sensors ◽

10.3390/s19030658 ◽

2019 ◽

Vol 19 (3) ◽

pp. 658 ◽

Cited By ~ 4

Author(s):

Víctor Ruiz-Díez ◽

Javier Toledo ◽

Jorge Hernando-García ◽

Abdallah Ababneh ◽

Helmut Seidel ◽

...

Keyword(s):

Resonant Frequency ◽

Quality Factor ◽

Q Factor ◽

Liquid Media ◽

Roof Tile ◽

Aln Film ◽

Monitoring Applications ◽

Media Monitoring ◽

Comprehensive Study

Cantilever resonators based on the roof tile-shaped modes have recently demonstrated their suitability for liquid media monitoring applications. The early studies have shown that certain combinations of dimensions and order of the mode can maximize the Q-factor, what might suggest a competition between two mechanisms of losses with different geometrical dependence. To provide more insight, a comprehensive study of the Q-factor and the resonant frequency of these modes in microcantilever resonators with lengths and widths between 250 and 3000 µm and thicknesses between 10 and 60 µm is presented. These modes can be efficiently excited by a thin piezoelectric AlN film and a properly designed top electrode layout. The electrical and optical characterization of the resonators are performed in liquid media and then their performance is evaluated in terms of quality factor and resonant frequency. A quality factor as high as 140 was measured in isopropanol for a 1000 × 900 × 10 µm3 cantilever oscillating in the 11th order roof tile-shaped mode at 4 MHz; density and viscosity resolutions of 10−6 g/mL and 10−4 mPa·s, respectively are estimated for a geometrically optimized cantilever resonating below 1 MHz.

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A Study on the Trimming Effects on the Quality Factor of Micro-Shell Resonators Vibrating in Wineglass Modes

Micromachines ◽

10.3390/mi10100695 ◽

2019 ◽

Vol 10 (10) ◽

pp. 695

Author(s):

Lu ◽

Xi ◽

Xiao ◽

Shi ◽

Zhuo ◽

...

Keyword(s):

Finite Element Method ◽

Quality Factor ◽

Second Harmonic ◽

Great Influence ◽

Fem Simulation ◽

Q Factor ◽

Thermoelastic Damping ◽

Frequency Trimming ◽

Quality Factor Q ◽

Anchor Loss

Frequency trimming based on mass and stiffness modification is an important post-fabrication process for micro-shell resonators (MSRs). However, the trimming effects on the quality factor are seldom studied, although they may have great influence on the performance of the resonator. This paper presents a study on the quality factor (Q-factor) variation of trimmed micro-shell resonators (MSR). Thermoelastic damping (QTED) and anchor loss (Qanchor) are found to be the dominant energy loss mechanisms resulting in the reduction of the overall Q-factor, according to finite element method (FEM). The effects of different trimming methods on QTED and Qanchor are studied here, respectively. It is found that trimming grooves ablated in the rim of the resonator can cause a ~1–10% reduction of QTED, and the length of trimming groove is positively related to the reduction of QTED. The reduction of QTED caused by the mass adding process is mainly related to the thermal expansion coefficient and density of the additive and contact area between the resonator and additive masses. Besides, the first and second harmonic errors caused by asymmetrical trimming can cause a 10–90% reduction of Qanchor. Finally, trimming experiments were conducted on different resonators and the results were compared with FEM simulation. The work presented in this paper could help to optimize the trimming process of MSRs.

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The Design and Simulation of Vibratory Ring Gyroscope

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.609-610.1029 ◽

2014 ◽

Vol 609-610 ◽

pp. 1029-1032 ◽

Cited By ~ 1

Author(s):

Mei Yu Meng ◽

Wen Dong Zhang

Keyword(s):

Modeling And Simulation ◽

Quality Factor ◽

Resonant State ◽

Vacuum Packaging ◽

Q Factor ◽

Wafer Level ◽

Temperature Drift ◽

High Quality ◽

Small Temperature ◽

Packaging Technology

This paper deals with design and simulation of vibratory ring gyroscope which has good performance as resisting vibration, resisting impact, small temperature drift because of the inherent symmetry of structure. The good performance of gyroscope has verified by detailed modeling and simulation. The manufacture of gyroscope using wafer level vacuum packaging technology making the gyroscope has high quality factor .At last we test the gyroscope and the Q factor is 20300 by detecting the resonant state of the gyroscope.

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Failure of an Uncemented Press-Fit Acetabular Cup in Primary Total Hip Arthroplasty

Hip International ◽

10.1177/112070000201200404 ◽

2002 ◽

Vol 12 (4) ◽

pp. 371-377 ◽

Cited By ~ 1

Author(s):

N. Rama Mohan ◽

P. Grigoris ◽

D.L. Hamblen

Keyword(s):

Femoral Stem ◽

Acetabular Cup ◽

Total Hip ◽

Press Fit ◽

Total Hip Replacements ◽

Locking Mechanism ◽

Hip Replacements ◽

The Mean ◽

Open Position ◽

Primary Total Hip Arthroplasty

We reviewed fifteen primary total hip replacements performed using the uncemented, non-porous coated press-fit AcSys Shearer Cup. A modular titanium straight femoral stem with a 32mm head was used in all cases. The mean age of the group containing five males and 10 females was 66 years. Eight cups have been revised for aseptic loosening at a mean of seven years and the remaining four cups are radiologically loose. At revision surgery none of the cups showed any evidence of bony ingrowth. Our 10-year results with this cup indicate an unacceptably high failure rate of 80%. Absence of bony ingrowth and the lack of a secure locking mechanism between the polyethylene liner and the metal shell are the most important causes of failure. The use of a 32mm diameter head and implantation of the cup in an open position contributed to this failure. Even though this cup is no longer manufactured, our experience suggests that all non-porous coated cups should be closely followed up.

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The quality factor of x-rays/gamma rays as one is realistic?

Journal of Radiotherapy in Practice ◽

10.1017/s1460396912000349 ◽

2012 ◽

Vol 11 (3) ◽

pp. 195-197 ◽

Cited By ~ 1

Author(s):

Syed F. Akber

Keyword(s):

Radiation Dose ◽

Energy Range ◽

Quality Factor ◽

Gamma Rays ◽

Specific Energy ◽

Biological Systems ◽

X Rays ◽

Radiation Quality ◽

Cell Cycles ◽

The Mean

AbstractThe quality factor for x-rays, gamma rays and electrons assigned as one need to be revised. It is observed that as the energy decreases, mean lethal radiation dose (Do)decreases as well and become more potent. It is therefore proposed that radiation quality in biological systems should be assessed in the mitotic phase of the cell cycles. Furthermore, based on the mean lethal radiation dose within specific energy range, an appropriate quality factor of x-rays, gamma rays and electrons should be assigned.

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Effect of Geometric Imperfections on Anchor Loss and Characterisation of a Gyroscope Resonator with High Quality Factor

Giroskopiya i Navigatsiya ◽

10.17285/0869-7035.0037 ◽

2020 ◽

Vol 28 (3) ◽

pp. 18-31

Author(s):

G.N. Sharma ◽

◽

Sundararajan T. ◽

G.S. Singh ◽

◽

...

Keyword(s):

Quality Factor ◽

Shell Thickness ◽

Sensitivity Study ◽

Thickness Variation ◽

Q Factor ◽

Surface Characterisation ◽

Geometric Imperfections ◽

Before And After ◽

Functional Part ◽

Anchor Loss

A critical functional part of a hemispherical resonator gyroscope (HRG) is the mechanical resonator, and a few million quality factor (Q-factor) is needed for the lowest resolution. This paper focuses on anchor loss of a HRG of a few millimeters in size. A detailed parametric study of dimensions and shell imperfections due to fabrication is carried out. A sensitivity study of the effect of shell mean radius, shell thickness, stem radius, stem height on the Qanchor is carried out. The effect of geometric imperfections such as shell offset, shell tilt, shell thickness variation, and unbalance is studied in detail. From the study, it is inferred that the anchor loss becomes very significant and approaches other loss mechanisms even with minor geometric imperfections in the hardware realisation. Based on the sensitivity study, the dimensional and geometric tolerances are arrived for precision fabrication. Precision resonator is fabricated as per the requirement of minimum anchor loss. The significance of other damping mechanisms such as air damping, excitationinduced damping, thermoelastic dynamic damping and surface dissipation is also discussed. Surface characterisation before and after surface treatment has been carried out using nanoindentation technique with regard to surface loss. Functional parameters of operating frequency and Q-factor are evaluated using laser Doppler vibrometry (LDV).

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On the Origins of Eccentric Close-in Planets

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308026409 ◽

2008 ◽

Vol 4 (S253) ◽

pp. 189-195 ◽

Cited By ~ 2

Author(s):

Soko Matsumura ◽

Genya Takeda ◽

Fred A. Rasio

Keyword(s):

Solar System ◽

Quality Factor ◽

Extrasolar Planets ◽

External Perturbation ◽

Central Star ◽

Circular Orbits ◽

Secular Perturbation ◽

New Class ◽

Stellar Ages ◽

Host Stars

AbstractStrong tidal interaction with the central star can circularize the orbits of close-in planets. With the standard tidal quality factorQof our solar system, estimated circularization timescales for close-in extrasolar planets are typically shorter than the age of the host stars. While most extrasolar planets with orbital radiia≲ 0.1 AU indeed have circular orbits, some close-in planets with substantial orbital eccentricities have recently been discovered. This new class of eccentric close-in planets implies that either their tidalQfactor is considerably higher, or circularization is prevented by an external perturbation. Here we constrain the tidalQfactor for transiting extrasolar planets by comparing their circularization times with accurately determined stellar ages. Using estimated secular perturbation timescales, we also provide constraints on the properties of hypothetical second planets exterior to the known eccentric close-in planets.

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