Dust exposure levels were studied in a cement factory in Dar es Salaam, Tanzania, as part of an epidemiological study assessing chronic respiratory health effects. One hundred and twenty personal 'total' dust samples were collected from 80 randomly selected workers from eight a priori occupational groups (OGs) based on work areas using a 37 mm Millipore sampler. The between-group, within-group ...

The allometric method, which often is attributed to Julian Huxley, entails fitting a straight line to logarithmic transformations of the original bivariate data and then back-transforming the resulting equation to form a power function in the arithmetic scale. Development of the technique was strongly influenced by Huxley's own research on growth by the enlarged 'crusher' claw in male fiddler c...

The effectiveness of jigging operation for the beneficiation of low-grade iron ore deposits of Orissa, India has been investigated. Iron ore sample obtained from Barbil region of Orissa containing very high amount of silica and alumina was crushed using the laboratory jaw crusher and roll crusher to prepare different particle sizes. The sink and float tests were carried out to evaluate the poss...

Abstract Coal is responsible for the generation of around 38 percent power that used throughout entire planet. In last two decades, there has been a rise in number chances recycling and usage fly ash from coal combustion due to its hydrophobic cementitious properties. However, still limited commercialization (CFA) road construction. The focus this research determine bearing capacity CFA-treated...

Driverless haulage trucks have recently been developed for open pit mines. To predict the benefits of an Autonomous Haulage System (AHS), a deterministic/stochastic model has been created to compare AHS to a manual system by estimating benchmarked Key Performance Indicators (KPIs) such as productivity, safety, breakdown frequencies, maintenance and labor costs, fuel consumption, tire wear, and ...

This paper describes the use of a multi-objectiveevolutionary algorithm to solve an engineeringdesign problem determining the geometry andoperating settings for a crusher in acomminution circuit for ore processing. Theoutcome is a tool for consulting engineers thatcan be used to create and explore candidatedesigns for various scenarios. The tool hasproved capable...

The inversion method was used to test vibroacoustic processes in large-size machines used in opencast mines of rock material. When this method is used, the tested machine is replaced with a set of substitute sources, whose acoustic parameters are determined on the basis of sound pressure levels and phase shift angles of acoustic signals, measured with an array of 24 microphones. This article pr...

The Al-alloying treated tungsten carbide (WC)-Co tool was subjected to grinding using a jaw crusher and planetary mill followed by three wet chemical treatment steps to establish an effective recycling process for WC scraps, especially those generated as bulky and hard scrap. This alloyed WC tool was readily ground to a powder of 1 mm or less and divided into two portions that were 150 μm in si...