Tar removal from biomass gasification gas is a crucial problem in applying syngas from biomass for its downstream applications. Catalytic biomass gasification has given promising results for tar cracking. A few research groups have investigated the use of olivine for tar cracking [2,3,4,7,8,9,10]. The presence of oxides of iron and magnesium in the mineral olivine give it the ability to crack h...

The relation of habitual knuckle cracking to osteoarthrosis with functional impairment of the hand has long been considered an old wives' tale without experimental support. The mechanical sequelae of knuckle cracking have been shown to produce the rapid release of energy in the form of sudden vibratory energy, much like the forces responsible for the destruction of hydraulic blades and ship pro...

Rockwall erosion by rockfall is largely controlled frost weathering in high alpine environments. As rock types are characterized crack-dominated porosity and strength, cracking observations from low strength grain supported pore-space rocks cannot be transferred. Here, we conducted laboratory experiments on Wetterstein limestone samples with different initial crack density saturation to test th...

A leak is an undesirable interconnection between isolated parts of a system or between two systems and is suspected if there is any abnormal behavior of a system, such as loss of pressure, contamination of product or loss of process efficiency. A leak in a system can occur due to an unintended crack, corrosion or porosity, hole in an enveloping wall, loosening of bolts/joints and cracking of ga...

Parameterized password guessability—how many guesses a particular cracking algorithm with particular training data would take to guess a password—has become a common metric of password security. Unlike statistical metrics, it aims to model real-world attackers and to provide per-password strength estimates. We investigate how cracking approaches often used by researchers compare to real-world c...

It is extremely difficult to predict the initiation time of cracking due to a large time spread in most cracking experiments. Thus, probabilistic models, such as the Weibull distribution, are usually employed to model the initiation time of cracking. Therefore, the parameters of the Weibull distribution are estimated from data collected from a cracking test. However, although the development of...

The mechanics of cracking in fiber-reinforced ceramic matrix composites (CMCs) under general loadings remains incomplete. The present paper addresses one outstanding aspect of this problem: the development of matrix cracks in unidirectional plies under shear loading. To this end, we develop a model based on potential energy differences upstream and downstream of a fully bridged steady-state mat...

ANALYTICAL AND EXPERIMENTAL STUDY OF INVESTMENT CASTING WITH LASER STEREOLITHOGRAPHY MODELS by Wen-Long Yao This dissertation presents an analytical and experimental investigation of ceramic shell cracking during the burnout process in investment casting with internally webbed laser stereolithography (SLA) patterns. Included in the consideration are the cracking temperature of the ceramic shell...