Thirteen repetitions of a cross-channel transect in the Khuran Channel within the Strait of Hormuz allowed the description of the mean flow and semidiurnal tidal properties of a northsouth transect. Water velocity profiles were obtained with a 614.4 kHz TRDI Work Horse Broadband ADCP along this 3.3 km long transect on 10 October 2014, the third day of secondary spring tide. The M2, M4 and M6 fr...

We study the offers submitted by consumers to a large Name-Your-Own-Price (NYOP) online retailer. A distinctive feature of this retailer is that it allows consumers to repeatedly submit offers on one and the same product. While consumers could identify the threshold price (the minimum price for which the retailer is willing to sell) by incrementing their offer in small steps in each consecutive...

Introduction: During sliding mechanics, frictional resistance is an important counterforce to orthodontic tooth movement; which must be controlled to allow application of light continuous forces. objective: To investigate static and kinetic frictional resistance between three orthodontic brackets: ceramic, self-ligating, and stainless steel, and three 0.019×0.025” archwires: stainless steel, ni...

The objective of this investigation was to assess and compare the in vitro tribological behaviour of four commercially available self-ligating bracket systems. The frictional characteristics of the Damon3, Speed, In-Ovation R, and Time2 bracket systems were studied using a jig that mimics the three-dimensional movements that occur during sliding mechanics. Each bracket system was tested on the ...

This study investigated the effects of a diamond-like carbon (DLC) coating on frictional and mechanical properties of orthodontic brackets. DLC films were deposited on stainless steel brackets using the plasma-based ion implantation/deposition (PBIID) method under two different atmospheric conditions. As-received metal brackets served as the control. Two sizes of stainless steel archwires, 0.01...

Static and dynamic frictional phenomena at the interface with random impurities are investigated in a two-chain model with incommensurate structure. Static frictional force is caused by the impurity pinning and/or by the pinning due to the regular potential, which is responsible for the breaking of analyticity transition for impurity-free cases. It is confirmed that the static frictional force ...

Hydraulic actuators have high power-to-weight ratios, making them suitable for high-power robotic applications such as in walking robots and construction machines. However, large frictional forces in hydraulic actuators, rotary hydraulic actuators in particular, degrade the control performance. To suppress frictional forces and increase robustness against modeling errors, this study considered ...

The friction and wear properties of polyamide 66 (PA66), polyphenylene sulfide (PPS) and polytetrafluoroethylene (PTFE) sliding against hemselves under dry sliding and oil-lubricated conditions were studied by using a pin-on-disc tribometer. The effect of applied load and sliding peed on tribological behaviors of the polymer–polymer sliding combinations under dry sliding and oil-lubricated cond...

Thirteen repetitions of a cross-channel transect in the Khuran Channel within the Strait of Hormuz allowed the description of the mean flow and semidiurnal tidal properties of a north-south transect. Water velocity profiles were obtained with a 614.4 kHz TRDI Work Horse Broadband ADCP along this 3.3 km long transect on 10 October 2014, the third day of secondary spring tide. The M2, M4 and M6 f...

To investigate polymer friction and the role of surface roughness on polymer tribology, microtribometry testing was performed using hydrocarbon films ranging in roughness from a molecularly smooth monolayer to extremely rough polymethylene coatings that were prepared on both the substrate (a flat silicon wafer) and the probe (a 6 mm borosilicate lens). The results show that the rough topography...