scholarly journals EFFECTIVENESS OF SOFT WALL CAPPING IN CONSERVING RUINS

2021 ◽  
Author(s):  
Richard Schlesinger
Keyword(s):  
Soft Wall

scholarly journals A reconfigurable soft wall-climbing robot actuated by electromagnet

2021 ◽  
Vol 18 (2) ◽  
pp. 172988142199228
Author(s):  
Wendong Zhang ◽  
Wen Zhang ◽  
Zhenguo Sun
Keyword(s):  
Working Conditions ◽  
Horizontal Plane ◽  
Vertical Wall ◽  
Flaw Detection ◽  
Surface Cleaning ◽  
Electromagnetic Actuator ◽  
Climbing Robot ◽  
Soft Wall ◽  
Power Frequency

This article demonstrates a reconfigurable soft wall-climbing robot actuated by electromagnet. The robot follows the earthworm movement gait and is capable of translation, deflection, and rotation movement while working on a sloping ferromagnetic wall. Also the electromagnetic actuator provides a significant improvement in expeditiousness compared with existing actuation modes. The speed of the robot can be adjusted by modulating the power frequency. When the period of motion cycle is 30 ms, the speed is about 26.5 mm s−1, and the robot can rotate with a velocity of 14.1° s−1 on the horizontal plane. It can also climb a vertical wall at the speed of 12.6 mm s−1. The robot is composed of two kinds of modules which can be connected by the magnets embedded. It can also be reconfigured in different working conditions, such as crossing an inaccessible gap, and thus has the potential to be used in flaw detection, surface cleaning, and exploration of ferromagnetic structures.

scholarly journals NUCLEON RESONANCES AND GPDS IN AdS/QCD

2014 ◽  
Vol 26 ◽  
pp. 1460066 ◽  
Author(s):  
ALFREDO VEGA ◽  
IVAN SCHMIDT ◽  
THOMAS GUTSCHE ◽  
VALERY E. LYUBOVITSKIJ
Keyword(s):  
Roper Resonance ◽  
Wall Model ◽  
Nucleon Resonances ◽  
Soft Wall Model ◽  
Nucleon Spectrum ◽  
Soft Wall

We discuss an holographic soft wall model to describe nucleon properties. We pay special attention to nucleon spectrum, GPDs in the skewness case for nucleons and electroproduction of the N (1440) Roper resonance in soft-wall AdS/QCD.

The density profile of a fluid bounded by a soft wall

1983 ◽  
Vol 79 (6) ◽  
pp. 3009-3017 ◽  
Author(s):  
Jerome K. Percus ◽  
G. O. Williams
Keyword(s):  
Density Profile ◽  
Soft Wall

Effect of viscoelasticity on the soft-wall transition and turbulence in a microchannel

2017 ◽  
Vol 812 ◽  
pp. 1076-1118 ◽  
Author(s):  
S. S. Srinivas ◽  
V. Kumaran
Keyword(s):  
Molecular Weight ◽  
Reynolds Number ◽  
Reynolds Stress ◽  
Mass Fraction ◽  
Rectangular Cross Section ◽  
Pure Water ◽  
Polymer Concentration ◽  
Wall Turbulence ◽  
Solution Viscosity ◽  
Soft Wall

The modification of soft-wall turbulence in a microchannel due to small amounts of polymer dissolved in water is experimentally studied. The microchannels are of rectangular cross-section with height ${\sim}$160 $\unicode[STIX]{x03BC}\text{m}$, width ${\sim}$1.5 mm and length ${\sim}$3 cm, with three walls made of hard polydimethylsiloxane (PDMS) gel, and one wall made of soft PDMS gel with an elasticity modulus of ${\sim}$18 kPa. Solutions of polyacrylamide of molecular weight $5\times 10^{6}$ and mass fraction up to 50 ppm, and of molecular weight $4\times 10^{4}$ and mass fraction up to 1500 ppm, are used in the experiments. In all cases, the solutions are in the dilute limit below the critical overlap concentration, and the solution viscosity does not exceed that of water by more than 10 %. Two distinct types of flow modifications are observed below and above a threshold mass fraction for the polymer, $w_{t}$, which is ${\sim}$1 ppm and 500 ppm for the solutions of polyacrylamide with molecular weights $5\times 10^{6}$ and $4\times 10^{4}$, respectively. At or below $w_{t}$, there is no change in the transition Reynolds number, but there is significant turbulence attenuation, by up to a factor of 2 in the root-mean-square velocities and a factor of 4 in the Reynolds stress. When the polymer concentration increases beyond $w_{t}$, there is a decrease in the transition Reynolds number and in the intensity of the turbulent fluctuations. The lowest transition Reynolds number is ${\sim}$35 for the solution of polyacrylamide with molecular weight $5\times 10^{6}$ and mass fraction 50 ppm (in contrast to 260–290 for pure water). The fluctuating velocities in the streamwise and cross-stream directions are lower by a factor of 5, and the Reynolds stress is lower by a factor of 10, in comparison to pure water.

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