Ferrographic analysis of wear particles from sliding elastohydrodynamic experiments

The Ferrograph was used to analyze wear debris generated in a sliding elastohydrodynamic contact. The amount of wear debris correlates well with the ratio of film thickness to composite surface roughness (A ratio). The general wear level parameter and the wear severity index yielded similar correlations with average A ratios. Essentially all the generated wear particles were of the normal rubbing wear type. The Ferrograph was more sensitive in detecting the wear debris than was the commonly used emission spectrograph

Ferrographic analysis of wear debris generated in a sliding elastohydrodynamic contact

The ferrograph was used to analyze wear debris generated in a sliding elastohydrodynamic contact. The amount of wear debris correlates well with the ratio of film thickness to composite surface roughness. Essentially all of the generated wear particles were of the normal rubbing wear type

Investigations of lubricant rheology as applied to elastohydrodynamic lubrication

Traction prediction in sliding elastohydrodynamic (EHD) contacts was examined along with an elastohydrodynamic lubrication simulation of the effects of load and speed on temperatures in the EHD contact. An existing shear stress theory and lubricant rheological model were studied and evaluated by applying them to traction prediction. Results obtained using measured film thickness and surface temperature data, were compared with measured traction values. The infrared technique for measuring temperatures in an EHD contact was further developed and ball surface and fluid temperatures are reported for sliding speeds of 0.35 to 5.08 m/s at 0.52 to 2.03 GN/sq m maximum pressure and surface roughnesses of .011 to .381 micrometers c.1.a. The relationship between asperity interaction, as measured by relocation surface profilimetry and high frequency temperature measurements, and the ratio of film thickness to surface roughness was also studied

Reference Distorted Prices

I show that when consumers (mis)perceive prices relative to reference prices, budgets turn out to be soft, prices tend to be lower and the average quality of goods sold decreases. These observations provide explanations for decentralized purchase decisions, for people being happy with a purchase even when they have paid their evaluation, and for why trade might affect high quality local firms 'unfairly'

Development of intuitive rules: Evaluating the application of the dual-system framework to understanding children's intuitive reasoning

This is an author-created version of this article. The original source of publication is Psychon Bull Rev. 2006 Dec;13(6):935-53 The final publication is available at www.springerlink.com Published version: http://dx.doi.org/10.3758/BF0321390

Some Performance Characteristics of Subsurface Gravel Wetlands for Stormwater Management

Subsurface gravel wetlands were originally purposed for wastewater treatment and more recently have been used for stormwater treatment as a green infrastructure technology. Systems are sized to hold the water quality volume above, and drain within 24–48 hours. Design guidance follows static sizing principles with very little hydraulic calculations, which has left a gap in hydraulic performance data. Data from 12 years of field monitoring of various systems constructed in the northeast United States is presented. These systems include fully-sized as well as undersized (hold less that the water quality volume). Hydraulics are controlled by a restrictive outlet. At the same time, this outlet also creates the wetland characteristics of the system. Pollutant removal efficiencies for common stormwater pollutants are some of the highest for green infrastructure systems, with a significant component being microbially-mediated in the low dissolved oxygen gravel layers. This is a book chapter published by the American Society of Civil Engineers in World Environmental and Water Resources Congress 2020: Emerging and Innovative Technologies and International Perspectives in 2020, available online: https://doi.org/10.1061/978078448294

High-resolution observations of tungsten liner collapse and early jet formation

High-resolution photography of collapsing tungsten-lined shaped charges has revealed surface texturing both similar to and strikingly different from that previously observed during copper liner collapse. The behavior of three types of tungsten-lined shaped charges, with different liner designs and high explosives but with similar tungsten processing, were characterized by image-converter camera and fast- framing camera photography, and flash x-ray radiography. 120-mm- diameter, trumpet-shaped Octol charges produced surface blistering near the base of the tungsten liner, probably due to inhomogeneities near the liner-explosive interface resulting from cast loading. 148- mm-diameter, quasi-conical LX-14 charges produced smooth shocked- surface texture similar to that observed in conical, copper-lined LX- 14 (Viper) charges. 81-mm-diameter, conical LX-20 charges produced severe radial texturing throughout the collapsing tungsten liner, which transitioned to azimuthal banding on the jet surface. For each type of charge, obscuring debris from the tungsten jet tip prevented clear imaging of the jet surface at late time. 8 refs., 6 figs., 2 tabs

Aromatase inhibitors as adjuvant therapy for postmenopausal women: a therapeutic advance but many unresolved questions

Adjuvant hormonal therapy for postmenopausal women with early stage breast cancer has become far more complex over the past several years. This commentary reviews the current status of the five major trials evaluating the use of the aromatase inhibitors in the adjuvant setting. The data currently available suggest that the aromatase inhibitors are efficacious either as upfront therapy or after a course of tamoxifen. Ongoing trials will compare these approaches and guide the use of these agents in the years to come

Enhanced enforcement of the foreign corrupt practices act: Improving the ethics of U.S. business practices abroad

Empirical research demonstrates that bribery has a detrimental impact on investment, economic growth, trade, and democratic governments. In response to rising bribery activity and the additional burdens placed on corporate officials by the Sarbanes-Oxley Act of 2002, enforcement of the Foreign Corrupt Practices Act (FCPA) of 1977 has reached an all-time high. Although many managers, financial officers, entrepreneurs, and auditors are aware of the FCPA\u27s objectives and mandates, many do not do an adequate job of protecting their firms, employees, and/or clients from fines and prison sentences. The purposes of this paper are to (1) analyze and describe bribery and FCPA case filings, sanctions, payments (bribes), and value of business to be obtained; (2) describe and analyze the important provisions of the FCPA; (3) discuss vicarious liability or the liability of U.S. firms and others for the acts of third parties; and (4) make recommendations to help firms improve their compliance with the FCPA. © 2012 by Emerald Group Publishing Limited

Fabry-Perot measurements and analysis of TOW-2A liner collapse and jet formation

A TOW-2A 146 mm shaped charge was fired and observed with five beam Fabry-Perot laser velocimetry. The liner collapse velocities were measured at five lines of sight covering the outer half of the liner. A record of 8-10 {mu}s in length was obtained for each sight line The velocity records at late time differ for each location, reflecting the varying charge-to-mass ratio as the end of the liner is approached. The results were analyzed with the CALE-2D hydrodynamic simulation code. The calculations reproduce the jump-off times, the shapes of the velocity jumps and the late time velocity asymptotes, but they underestimate the jump-off velocities by 6-7%. The calculations show that there exist no features in the velocity records that require spallation to account for them. Rather, the standard Steinberg-Guinan material model adequately accounts for the response of this copper liner to LX-14