Predicted and observed behaviour of pre-installed barriers for the mitigation of tunnelling effects

2021 ◽  
Vol 118 ◽  
pp. 104200
Author(s):  
Luca Masini ◽  
Sebastiano Rampello
Keyword(s):  
Observed Behaviour ◽  
Tunnelling Effects

An experimental study of the influence of heat storage and transportability of different lubricants on friction under transient elastohydrodynamic conditions

2003 ◽  
Vol 217 (1) ◽  
pp. 27-37 ◽  
Author(s):  
B-O Åhrström ◽  
C Penchinat ◽  
T Norrby
Keyword(s):  
Heat Storage ◽  
Improve Performance ◽  
Dynamic Simulations ◽  
Successful Model ◽  
Frictional Properties ◽  
Fast Fourier Transform Analysis ◽  
Propagating Waves ◽  
Frictional Forces ◽  
Observed Behaviour ◽  
Reduce Emissions

Lubricated transient elastohydrodynamic (EHD) conjunctions are extremely difficult to simulate numerically since lubricant properties such as temperature and viscosity vary significantly during the loading-unloading event. Nevertheless, industry has invested considerable time and effort in trying to create such models in order to improve performance and to reduce emissions and friction. One of the essential requirements for a successful model is accuracy in the implementation of frictional properties. The experimental method presented in this paper used an impact on the end surface of a beam to generate propagating waves that were subjected to fast Fourier transform analysis. The method yielded detailed information about the build-up and decay of normal and frictional forces as a function of time for various lubricants at three different initial temperatures (20, 40 and 80°C) and at relevant EHD pressures. A variety of lubricants were studied to a peak Hertzian pressure of 2.5GPa for loading-unloading times of 200-400 μs (typical for elastohydrodynamically lubricated conjunctions in ball bearings and gears). A qualitative study of the thermal properties of the lubricants and their influence on viscosity and friction coefficient was also undertaken and, finally, a plausible explanation of the observed behaviour is presented and parallels to dynamic simulations of polyatomic gases are drawn.

The Deception Study: A Potential Paradigm for the Evaluation of Generalizability of Social Skills Training

1985 ◽  
Vol 13 (4) ◽  
pp. 342-348
Author(s):  
Kevin Wheldall ◽  
Richard Alexander
Keyword(s):  
Social Skills ◽  
Classroom Management ◽  
Educational Psychology ◽  
Social Skills Training ◽  
Skills Training ◽  
Academic Skills ◽  
Evaluation Methodology ◽  
Observed Behaviour ◽  
Per Se ◽  
Contemporary Educational Psychology

Research into social skills training has, in common with much other contemporary educational psychology practice, been beset by the problem of how best to evaluate effectiveness. Alongside the movement towards more behaviourally inclined approaches has grown a dissatisfaction with the traditional methods of evaluting effectiveness. If we recognize behaviour per se as being the appropriate level for intervention, whether in relation to academic skills teaching, classroom management, social skills training or whatever, then it follows that effectiveness can only logically be assessed in terms of measurable changes in observed behaviour. Evaluation methodology has tended to lag behind interventional methodology, however, so that it has not been uncommon to see behavioural work assessed in terms of changes in attitude and/or knowledge. On occasion evaluation is not even attempted and behaviour change is assumed to generalize outside the specific confines of the intervention situation.

The Influence of Environmental Factors on Daily Behaviour

1982 ◽  
Vol 14 (9) ◽  
pp. 1175-1193 ◽  
Author(s):  
R Herz
Keyword(s):  
Social Sciences ◽  
Physical Environment ◽  
Town Planning ◽  
Target Groups ◽  
Subjective Perceptions ◽  
Demand Models ◽  
Long Time ◽  
Observed Behaviour ◽  
The Individual ◽  
Transport Mobility

The question of the extent to which the concrete physical environment allows, causes, or even forces certain forms of behaviour to occur has been excluded from social sciences literature for a long time. More recent studies from environmental psychology show that the built environment, filtered by subjective perceptions, very probably influences the experience and actions of individuals. Town planning and transport planning is orientated towards the needs, demands, or simply the observed behaviour of social groups, segments of the population, and target groups of individuals. However, at this level the evidence about whether a spatiospecific determinant should be added to the sociodemographic, sociocultural, or socioeconomic determinants is very inconclusive. This paper investigates the influence of certain types of area on behaviour, and uses about 70000 weekday records at the level of differentiated groups of people. Everyday behaviour of the groups is quantified by their time budgets and daily programmes with broad groupings of out-of-house activities as well as various indicators of transport mobility. This study shows that with given characteristics of the individual and his household a series of behavioural parameters does not vary in space and thus these parameters can be used as input for behaviourally orientated transport demand models and transferred from one planning area to another.

Tunnelling Effects of Solitons in Optical Fibers with Higher-Order Effects

2012 ◽  
Vol 67 (6-7) ◽  
pp. 338-346
Author(s):  
Chao-Qing Dai ◽  
Hai-Ping Zhu ◽  
Chun-Long Zheng
Keyword(s):  
Optical Fibers ◽  
Schrodinger Equation ◽  
Soliton Solutions ◽  
Higher Order ◽  
Order Effects ◽  
Bright Solitons ◽  
Dark Solitons ◽  
Tunnelling Effect ◽  
Tunnelling Effects ◽  
Higher Order Effects

We construct four types of analytical soliton solutions for the higher-order nonlinear Schrödinger equation with distributed coefficients. These solutions include bright solitons, dark solitons, combined solitons, and M-shaped solitons. Moreover, the explicit functions which describe the evolution of the width, peak, and phase are discussed exactly.We finally discuss the nonlinear soliton tunnelling effect for four types of femtosecond solitons

Effects of wildfire on national park visitation and the regional economy: a natural experiment in the Northern Rockies

2013 ◽  
Vol 22 (8) ◽  
pp. 1155 ◽  
Author(s):  
John W. Duffield ◽  
Chris J. Neher ◽  
David A. Patterson ◽  
Aaron M. Deskins
Keyword(s):  
United States ◽  
National Park ◽  
Net Present Value ◽  
Wildland Fire ◽  
The United States ◽  
Management Policy ◽  
Demand Models ◽  
Value Loss ◽  
Park Service ◽  
Observed Behaviour

Federal wildland fire management policy in the United States directs the use of value-based methods to guide priorities. However, the economic literature on the effect of wildland fire on nonmarket uses, such as recreation, is limited. This paper introduces a new approach to measuring the effect of wildfire on recreational use by utilising newly available long-term datasets on the location and size of wildland fire in the United States and observed behaviour over time as revealed through comprehensive National Park Service (NPS) visitor data. We estimate travel cost economic demand models that can be aggregated at the site-landscape level for Yellowstone National Park (YNP). The marginal recreation benefit per acre of fire avoided in, or proximate to, the park is US$43.82 per acre (US$108.29 per hectare) and the net present value loss for the 1986–2011 period is estimated to be US$206 million. We also estimate marginal regional economic impacts at US$36.69 per acre (US$90.66 per hectare) and US$159 million based on foregone non-resident spending in the 17-county Great Yellowstone Area (GYA). These methods are applicable where time-series recreation data exist, such as for other parks and ecosystems represented in the 397-unit NPS system.

Seismic Response of URM Walls Strengthened with FRP Reinforced Coating

2017 ◽  
Vol 747 ◽  
pp. 612-619
Author(s):  
Petra Triller ◽  
Miha Tomaževič ◽  
Matija Gams
Keyword(s):  
Glass Fiber ◽  
Fiber Reinforced Polymer ◽  
Fiber Reinforced ◽  
Glass Fiber Reinforced Polymer ◽  
Displacement Capacity ◽  
Reinforced Polymer ◽  
Glass Fiber Reinforced ◽  
Shear Type ◽  
Observed Behaviour ◽  
Textile Reinforced Mortar

A set of individual URM walls as well as an assemblage of a three-storey URM hollow clay block masonry structure composed of two shear- and two cross-walls have been tested in original and strengthened state. As a method of strengthening, the coating of the walls, consisting of glass fiber reinforced polymer (GFRP) grid laid in fiber reinforced cementitious mortar matrix (sometimes called textile reinforced mortar), anchored to the walls with glass fiber anchors, has been used. All specimens were subjected to constant vertical load simulating the effect of gravity loads and cyclic horizontal displacements with step-wise increased amplitudes, induced either at the top of the walls or at the floor levels of the assemblage, simulating the effect of seismic loads.The observed behaviour and failure mechanisms were of the shear type. The results show that by the application of FRP reinforced coatings, the seismic performance of URM structures can be significantly improved. As the results of experiments indicate, the energy dissipation, displacement capacity and shear resistance of URM increase substantially. In this regard, adequate anchoring of coating to the masonry and into the r.c. floor structures is essential.

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