OBJECTIVE A shovel with a blade perforated with small holes was tested to see whether a worker would use less whole-body energy to dig wet clay than with a shovel with an opaque blade. BACKGROUND A perforated shovel is hypothesized to require less whole-body energy on the basis of adhesion theory; a smaller surface area would require less physical effort to dig and release soil from the blade...

Material excavation is the primary activity in surface mining operations; and shovel excavators are the primary production equipment in mining industry. The active population of cable shovels is about 2400 units around the world out of which 1700 are 20mt or larger capacity (http://parkerbaymining.com/mining-equipment/ electric-shovels.htm). Joy Global (P&H), Caterpillar (formerly under Bucyrus...

Most engineering artifacts behave in a continuous fashion, and this property is generally believed to underlie their dependability. In contrast, software systems do not have continuous behavior, which is taken to be an underlying cause of their undependability. The theory of software reliability has been questioned because technically the sampling on which it is based applies only to continuous...

The US coal mining industry consumes approximately 142 billion kWh per year of energy. The US Department of Energy estimates that the industry‟s annual energy consumption can be reduced by 49% (24.6 billion kWh/year by using currently available best practices and a further 44.8 billion kWh/year with more research). This constitutes nearly $3.7 billion of potential savings on coal production cos...

Electric cable shovel excavator is widely used in the surface mining operations of oil sand and other highly abrasive formations. The oil sands mines in Alberta use P&H 4100 C Boss shovel [1,2] for their loading operations. The lower works of this shovel consist of propel and crawler systems [3-7]. The crawler system consists of a crawler track assembly, front and rear idlers, lower rollers and...

Electric cable shovel excavator is widely used in the surface mining operations of oil sand and other highly abrasive formations. The oil sands mines in Alberta use P&H 4100 C Boss shovel [1,2] for their loading operations. The lower works of this shovel consist of propel and crawler systems [3-7]. The crawler system consists of a crawler track assembly, front and rear idlers, lower rollers and...

Chinese populations differ from Caucasoids by having a high prevalence of shovel trait and a low prevalence of Carabelli's trait. This study was conducted to investigate the association between the shovel and the Carabelli's traits in a Chinese population. The research design investigated a Chinese population that resides in southern Taiwan. The ancestors of this Chinese population migrated to ...

An analytical algorithm for the estimation of the resistance forces exerted on the dipper of a cable shovel and the specific energy consumed in the cutting-loading process is presented. Forces due to payload and to cutting of geomaterials under given initial conditions, cutting trajectory of the bucket, bucket’s design, and geomaterial properties are analytically computed. The excavation proces...

In Europe and North America, approximately 150 fatalities occur as a result of avalanches every year. However, it is unclear whether certain shovel shapes are more effective than others in snow removal during avalanche victim recovery. The objective was to determine the performance parameters with a developed standardized test using different shovel shapes and to determine sex-specific differen...