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Abstract: Most of the developing countries across the world have opened up their mining industry for private sector participation since late 1980s with a view to increase the overall efficiency of the mineral extraction. But are the private mining firms really efficient than the public sector firms? In such a context this paper compares the extraction efficiency of public and private mining firms in India by assessing their Total Factor Productivity (TFP). The study reveals that TFP levels of private firms are significantly higher than that of public firms in metallic, non-metallic and coal mining sectors. TFP levels of private firms in non-metallic sector are almost double that of public firms. Similarly, private firms in metallic and coal mining industry are one and half times more productive than public firms. In such a context, we can suggest that private participation in the mining industry may boost the overall productivity of the sector. [Copyright &y& Elsevier]

Abstract: Both GPS and inertial measurement units (IMUs) have been extensively used in biomechanical studies. Expensive high accuracy GPS units can provide information about intrastride speed and position, but their application is limited by their size and cost. Single and double integration of acceleration from IMU provides information about short-term fluctuations in speed and position, but suffers from integration error over a longer period of time. The integration of GPS and IMU has been widely used in large and expensive units designed for survey and vehicle navigation. Here we propose a data fusion scheme, which is a Kalman filter based complementary filter and enhances the frequency response of the GPS and IMU used alone. We also report the design of a small (28g) low cost GPS/IMU unit. Its accuracy after post-processing with the proposed data fusion scheme for determining average speed and intrastride variation was compared to a traditional high cost survey GPS. The low cost unit achieved an accuracy of 0.15ms−1 (s.d.) for horizontal speed in cycling and human running across a speed range of 3–10ms−1. The stride frequency and vertical displacement calculated based on measurements from the low cost GPS/IMU units had an s.d. of 0.08Hz and 0.02m respectively, compared to measurements from high performance OEM4 GPS units. [Copyright &y& Elsevier]

Abstract: This paper reports a study of the patterns of productivity changes in 25 regional airports in China during the period 1995–2004. We found the average annual growth in airport productivity to be above 3%. By the decomposition of the Malmquist index, we identified the major source of productivity growth to be technical progress, rather than an improvement in efficiency. The kernel smoothing method revealed a trend of disparate productivity among the airports that was due to the polarization of efficiency. Our results imply that reform policies should focus on non-hub airports, non-listed airports, and airports in the northeast region if more balanced development is to be achieved. [Copyright &y& Elsevier]

Abstract: This paper documents the comparative productivity performance of the United States and Britain since 1870, showing the importance of developments in services. We identify the transition in market services from customised, low-volume, high-margin business organised on a network basis to standardised, high-volume, low-margin business with hierarchical management, as a key factor. A model of the interaction between technology, organisation and economic performance is then provided, focusing on the transition from networks to hierarchies. Four general lessons are drawn: (1) developments in services must be analysed if the major changes in comparative productivity performance among nations are to be understood fully; (2) different technologies and organisational forms can co-exist efficiently; (3) technological change can cause difficulties of adjustment in technology-using sectors if it is not suited to the social capabilities of the society; (4) reversal of technological trends can lead to reversal of comparative productivity performance. [Copyright &y& Elsevier]