Suppression of vortex-induced high-mode vibrations of a cable-damper system by an additional damper

Clinical Relevance Shortened light curing does not affect volumetric polymerization shrinkage or cohesive tensile strength but negatively affects the shear bond strength of some bulk-fill resin composites. When performing shortened light curing, clinicians should be aware of the light output of their light-curing units. SUMMARY Purpose: To evaluate volumetric polymerization shrinkage (VPS), shear bond strength (SBS) to dentin, and cohesive tensile strength (CTS) of bulk-fill resin composites (BFRCs) light activated by different modes. Methods and Materials: Six groups were evaluated: Tetric EvoCeram bulk fill + high mode (10 seconds; TEC H10), Tetric EvoFlow bulk fill + high mode (TEF H10), experimental bulk fill + high mode (TEE H10), Tetric EvoCeram bulk fill + turbo mode (five seconds; TEC T5), Tetric EvoFlow bulk fill + turbo mode (TEF T5), and experimental bulk fill + turbo mode (TEE T5). Bluephase Style 20i and Adhese Universal Vivapen were used for all groups. All BFRC samples were built up on human molar bur-prepared occlusal cavities. VPS% and location were evaluated through micro–computed tomography. SBS and CTS tests were performed 24 hours after storage or after 5000 thermal cycles; fracture mode was analyzed for SBS. Results: Both TEC H10 and TEE H10 presented lower VPS% than TEF H10. However, no significant differences were observed with the turbo-curing mode. No differences were observed for the same BFRC within curing modes. Occlusal shrinkage was mostly observed. Regarding SBS, thermal cycling (TC) affected all groups. Without TC, all groups showed higher SBS values for high mode than turbo mode, while with TC, only TEC showed decreased SBS from high mode to turbo modes; modes of fracture were predominantly adhesive. For CTS, TC affected all groups except TEE H10. In general, no differences were observed between groups when comparing the curing modes. Conclusions: Increased light output with a shortened curing time did not jeopardize the VPS and SBS properties of the BFRCs, although a decreased SBS was observed in some groups. TEE generally showed similar or improved values for the tested properties in a shortened light-curing time. The VPS was mostly affected by the materials tested, whereas the SBS was affected by the materials, curing modes, and TC. The CTS was not affected by the curing modes.

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Influence of High Mode Effects on Ductility Reduction Factors for MDOF Shear-Type Structures

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.578-579.412 ◽

2014 ◽

Vol 578-579 ◽

pp. 412-416

Author(s):

Hui Ying Wang

Keyword(s):

Time History ◽

Degree Of Freedom ◽

High Mode ◽

Lumped Mass ◽

Ductility Demand ◽

Mdof Systems ◽

Mode Effect ◽

Modification Factor ◽

Shear Type ◽

Reduction Factors

The influences of high mode effect on ductility reduction factors for multi-degree-of-freedom (MDOF) systems are studied by modifying ductility reduction factors for equivalent single-degree-of-freedom (SDOF) systems. Based on MDOF lumped-mass shear-type models, nonlinear dynamic time history analysis are performed to investigate the influence of ductility demand increase owing to high mode effect on ductility reduction factors. An empirical estimating model of MDOF modification factor is proposed. The results demonstrate that ductility reduction factors for MDOF systems are clearly smaller than those for SDOF systems. The modification factor is mainly affected by the fundamental period and ductility.

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MR-monitored focused ultrasound using the acoustic-coupling water bath as an intrinsic high-mode dielectric resonator

NMR in Biomedicine ◽

10.1002/nbm.3120 ◽

2014 ◽

Vol 27 (6) ◽

pp. 621-624 ◽

Cited By ~ 1

Author(s):

A. G. Webb

Keyword(s):

Dielectric Resonator ◽

Focused Ultrasound ◽

Water Bath ◽

High Mode ◽

Acoustic Coupling

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A Broadband Multi-OAM-Mode Four-Feed Circular Patch Antenna with High Mode Purity

2018 IEEE Asia-Pacific Conference on Antennas and Propagation (APCAP) ◽

10.1109/apcap.2018.8538154 ◽

2018 ◽

Cited By ~ 1

Author(s):

Yuhan Huang ◽

Zihang Qi ◽

Qingwen Li ◽

Hua Zhu ◽

Xiuping Li ◽

...

Keyword(s):

Patch Antenna ◽

High Mode ◽

Circular Patch ◽

Circular Patch Antenna ◽

Mode Purity

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Estimation of Hydrodynamic Coefficients for VIV of Slender Beam at High Mode Orders

29th International Conference on Ocean, Offshore and Arctic Engineering: Volume 6 ◽

10.1115/omae2010-20327 ◽

2010 ◽

Cited By ~ 3

Author(s):

Jie Wu ◽

Carl M. Larsen ◽

Halvor Lie

Keyword(s):

Modal Analysis ◽

Traveling Waves ◽

Flow Direction ◽

Research Effort ◽

Cross Flow ◽

Bending Moment ◽

Hydrodynamic Forces ◽

High Mode ◽

Excitation Region ◽

Inverse Force

The Hano̸ytangen test program was caried out by MARINTEK for Norsk Hydro in 1997. One purpose of this research effort was to investigate VIV response of deep sea risers subjected to sheared current. A densely instrumented 90 meter long riser model was tested in shear current, and bending strains along the riser was measured. Oscillatory part of both in-line (IL) and cross-flow (CF) displacements can be obtained by applying modal analysis on the bending moment measurements. The primary results from the analysis are that the riser is vibrating at high modes in cross-flow direction (10th–30th mode). The response is dominated standing waves for the lowest speed cases and gradually is influenced by traveling waves for increasing speed. For highest speed cases, it is dominated by traveling waves. The vibration amplitude is significantly smaller than for a rigid cylinder under equivalent conditions. Inverse force analysis estimates hydrodynamic forces from measured response of a slender beam. The method has previously been applied to rotating rig test data. The response was for these cases dominated by relatively low mode orders and standing wave responses. To understand the stochastic behaviour of high mode VIV response, the method is applied to Hano̸ytangen test in the present study to provide valuable insights by estimating CF hydrodynamic forces and coefficients from displacement time series found from modal analysis of measured strains. The results from this work are presented in terms of CF hydrodynamic force coefficients, excitation region and their variations in time and space. New excitation database is extracted based on the analysis results. They are used in VIVANA to predict the displacement and stress against experiment results.

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