ield tests were conducted to measure the effects of high concentrations of cement dust on the penetration and pressure drop of N95 electret respirator filters from two manufacturers. Three groups of each manufacturer’s filter were tested: 1) untreated; 2) irradiated with ionizing radiation; 3) dipped in isopropanol for 15 seconds. The purpose of the irradiation and isopropanol treatments was to...

The first signs of mobile commerce hype are here. Extremely rapid penetration and growth processes are predicted on the basis of some quick descriptions of mobile technology. The roots of these predictions are often found in markets with a low penetration rate of mobile technology. Nevertheless, it should be clear that without real substance in m-commerce products and services the investments i...

This paper gives an overview on the potentials of numerical simulations for understanding dynamics in laser material processing. After a short introduction into the model, simulation results on several processes like laser beam deep penetration welding, drilling or cutting are presented. Furthermore simulation results are compared with experimentally obtained data.

This paper analyzes the impact on mobile telephony diffusion patterns of the two predominant payment regimes, calling party pays (CPP) and receiving party pays (RPP), for mobile termination services. By applying instrumental variable techniques to panel data we account for a possible interdependency of penetration rates and regulatory interventions. For this purpose we use data on political and...

It is important for search and pay-per-click engines to penetration test their click fraud detection systems, in order to find potential vulnerabilities and correct them before fraudsters can exploit them. In this paper, we describe: (1) some goals and desirable qualities of a click fraud penetration testing system, based on our experience, and (2) our experiences with the challenges of buildin...

Soil stiffness constants govern the soil sinkage and the pressure-sinkage behaviour of the soil under load. To determine soil stiffness constants in Upadhyaya model under field conditions, a field reflecting general character of an agricultural soil was selected and multiplate penetration tests were conducted. The soil stiffness constants in Upadhyaya model were determined from five sets of soi...

PURPOSE To elucidate the spatial distribution of inactivation of lactate dehydrogenase (LDH) in ultraviolet-B radiation (UVR-B)-exposed eyes. To determine the in vivo penetration depth of UVR-B in the lens. METHODS LDH activity in cornea and lens was investigated with an enzyme histochemical technique. Thirty rats were exposed in vivo to UVR-B of approximately 300 nm, and the eyes were enucle...

Spaceborne Synthetic Aperture Radar (SAR) interferometry has been utilised to acquire high-resolution Digital Elevation Models (DEMs) with wide coverage, particularly for persistently cloud-covered regions where stereophotogrammetry is hard to apply. Since the discovery of sand buried drainage systems by the Shuttle Imaging Radar-A (SIR-A) L-band mission in 1982, radar images have been exploite...

In this work, we define a new metric of the distance and depth of penetration between two convex polyhedral bodies. The metric is computed by means of a linear program with three variables and m+n constraints, where m and n are the number of facets of the two polyhedral bodies. As a result, this metric can be computed with O(n+m) algorithmic complexity, superior to the best algorithms known for...

abstract different definitions have been proposed for soil quality. various soil properties have been suggetsted as soil quality indices by researchers. this research was conducted to study the relationship between slope of retention curve at its inflection point (s index) and other soil physical quality indices, because the reserches between s index and soil physical properties are little. thi...