scholarly journals Grinding investigation on three samples of sandstone from Canada Cement Company Limited, Exshaw, Alberta

1963 ◽  
Author(s):  
T F Berry
Keyword(s):  
Company Limited ◽  
Three Samples

An Adapted Measure of Teacher Self-Efficacy for Preservice Teachers: Exploring its Validity Across two Countries

2014 ◽  
Vol 28 (3) ◽  
pp. 83-92 ◽  
Author(s):  
Franziska Pfitzner-Eden ◽  
Felicitas Thiel ◽  
Jenny Horsley
Keyword(s):  
Preservice Teachers ◽  
Self Efficacy ◽  
Confirmatory Factor Analyses ◽  
3 Dimensional ◽  
Multiple Group ◽  
Three Samples ◽  
Confirmatory Factor ◽  
Teacher Self Efficacy ◽  
Dimensional Assessment ◽  
Metric Measurement

Teacher self-efficacy (TSE) is an important construct in the prediction of positive student and teacher outcomes. However, problems with its measurement have persisted, often through confounding TSE with other constructs. This research introduces an adapted TSE instrument for preservice teachers, which is closely aligned with self-efficacy experts' recommendations for measuring self-efficacy, and based on a widely used measure of TSE. We provide first evidence of construct validity for this instrument. Participants were 851 preservice teachers in three samples from Germany and New Zealand. Results of the multiple-group confirmatory factor analyses showed a uniform 3-factor solution for all samples, metric measurement invariance, and a consistent and moderate correlation between TSE and a measure of general self-efficacy across all samples. Despite limitations to this study, there is some first evidence that this measure allows for a valid 3-dimensional assessment of TSE in preservice teachers.

Perceived Mutual Understanding (PMU)

2019 ◽  
Vol 35 (1) ◽  
pp. 98-108 ◽  
Author(s):  
Michael J. Burtscher ◽  
Jeannette Oostlander
Keyword(s):  
Mutual Understanding ◽  
Team Cognition ◽  
Internal Reliability ◽  
Confirmatory Factor Analyses ◽  
Team Processes ◽  
One Dimensional ◽  
Item Parameters ◽  
Three Samples ◽  
Confirmatory Factor ◽  
The Individual

Abstract. Team cognition plays an important role in predicting team processes and outcomes. Thus far, research has focused on structured cognition while paying little attention to perceptual cognition. The lack of research on perceptual team cognition can be attributed to the absence of an appropriate measure. To address this gap, we introduce the construct of perceived mutual understanding (PMU) as a type of perceptual team cognition and describe the development of a respective measure – the PMU-scale. Based on three samples from different team settings ( NTotal = 566), our findings show that the scale has good psychometric properties – both at the individual as well as at the team-level. Item parameters were improved during a multistage process. Exploratory as well as confirmatory factor analyses indicate that PMU is a one-dimensional construct. The scale demonstrates sufficient internal reliability. Correlational analyses provide initial proof of construct validity. Finally, common indicators for inter-rater reliability and inter-rater agreement suggest that treating PMU as a team-level construct is justified. The PMU-scale represents a convenient and versatile measure that will potentially foster empirical research on perceptual team cognition and thereby contribute to the advancement of team cognition research in general.

The Relation Between Financial Incentives, Motivation, and Performance

2017 ◽  
Vol 16 (2) ◽  
pp. 61-76 ◽  
Author(s):  
Anaïs Thibault Landry ◽  
Marylène Gagné ◽  
Jacques Forest ◽  
Sylvie Guerrero ◽  
Michel Séguin ◽  
...  
Keyword(s):  
Financial Incentives ◽  
Work Performance ◽  
Autonomous Motivation ◽  
Compensation Plans ◽  
Work Settings ◽  
Path Analyses ◽  
Three Samples ◽  
And Performance ◽  
Performance Results

Abstract. To this day, researchers are debating the adequacy of using financial incentives to bolster performance in work settings. Our goal was to contribute to current understanding by considering the moderating role of distributive justice in the relation between financial incentives, motivation, and performance. Based on self-determination theory, we hypothesized that when bonuses are fairly distributed, using financial incentives makes employees feel more competent and autonomous, which in turn fosters greater autonomous motivation and lower controlled motivation, and better work performance. Results from path analyses in three samples supported our hypotheses, suggesting that the effect of financial incentives is contextual, and that compensation plans using financial incentives and bonuses can be effective when properly managed.

Investment for survival: Culter Mills Paper Company Limited, 1865–1914

1982 ◽  
Vol 5 (First Series (1) ◽  
pp. 31-56
Author(s):  
J. Neville Bartlett
Keyword(s):  
Company Limited ◽  
Paper Company

A geometallurgical characterization study of the Crystalkop Reef at the Great Noligwa Mine, Klerksdorp Goldfield, South Africa

2017 ◽  
Vol 120 (3) ◽  
pp. 303-322
Author(s):  
D. Pienaar ◽  
B.M. Guy ◽  
C. Pienaar ◽  
K.S. Viljoen
Keyword(s):  
South Africa ◽  
Treatment Plant ◽  
Processing Parameters ◽  
Processing Plant ◽  
Small Contribution ◽  
Gold Cyanide ◽  
Three Samples ◽  
Characterization Study ◽  
Different Sources

Abstract Mineralogical and textural variability of ores from different sources commonly leads to processing inefficiencies, particularly when a processing plant is designed to treat ore from a single source (i.e. ore of a relatively uniform composition). The bulk of the Witwatersrand ore in the Klerksdorp goldfield, processed at the AngloGold Ashanti Great Noligwa treatment plant, is derived from the Vaal Reef (>90%), with a comparatively small contribution obtained from the Crystalkop Reef (or C-Reef). Despite the uneven contribution, it is of critical importance to ensure that the processing parameters are optimized for the treatment of both the Vaal and C-Reefs. This paper serves to document the results of a geometallurgical study of the C-Reef at the Great Noligwa gold mine in the Klerksdorp goldfield of South Africa, with the primary aim of assessing the suitability of the processing parameters that are in use at the Great Noligwa plant. The paper also draws comparisons between the C-Reef and the Vaal Reef A-facies (Vaal Reef) and attempts to explain minor differences in the recovery of gold and uranium from these two sources. Three samples of the C-Reef were collected in-situ from the underground operations at Great Noligwa mine for mineralogical analyses and metallurgical tests. Laboratory-scale leach tests for gold (cyanide) and uranium (sulphuric acid) were carried out using dissolution conditions similar to that in use at the Great Noligwa plant, followed by further diagnostic leaching in the case of gold. The gold in the ore was found to be readily leachable with recoveries ranging from 95% to 97% (as opposed to 89% to 93% for the Vaal Reef). Additional recoveries were achieved in the presence of excess cyanide (96% to 98%). The recovery of uranium varied between 72% and 76% (as opposed to 30% to 64% for the Vaal Reef), which is substantially higher than predicted, given the amount of brannerite in the ore, which is generally regarded as refractory. Thus, the higher uranium recoveries from the C-Reef imply that a proportion of the uranium was recovered by the partial dissolution of brannerite. As the Vaal Reef contain high amounts of chlorite (3% to 8%), which is an important acid consumer, it is considered likely that this could have reduced the effectiveness of the H2SO4 leach in the case of the ore of the Vaal Reef. Since the gold and uranium recoveries from the C-Reef were higher than the recoveries from the Vaal Reef, the results demonstrate that the processing parameters used for treatment of the Vaal Reef are equally suited to the treatment of the C-Reef. Moreover, small processing modifications, such as increased milling and leach retention times, may well increase the recovery of gold (particularly when e.g. coarse gold, or unexposed gold, is present).

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