Productivity Growth in China's Agriculture During 1985-2010

This paper made an empirical analysis of China＇s agricultural growth path and influential factors using the province-level panel data of agricultural inputs and outputs during 1985-2010.The findings indicate that the increase in agricultural inputs and TFP contributed 40.6 and 55.2% to the agricultural output growth,respectively;China＇s agriculture had jumped out of the pattern which output growth was mainly driven by increasing input.Of the total inputs,chemical fertilizer had the most important contribution to the output growth,followed by mechanical inputs.The contribution of land and labor was negative.China＇s agricultural output growth belonged to the type of induced technology innovation.China＇s agricultural TFP growth had characteristics of fluctuations over time and unbalanced between regions,but the gap between the eastern,the middle,and the western regions has been narrowed.

Assessment of the Wind Energy Potential of Two Burundian Sites

1-year hourly wind speed data from two Burundian stations, namely Bujumbura and Muyinga, have been processed in this work to bring an efficient help for the planning and installation of wind energy conversion systems (WECS) at those localities. Mean seasonal and diurnal variations of wind direction and wind shear exponent have been derived. Two-parameter Weibull probability density functions (PDFs) fitting the observed monthly and annual wind speed relative frequency distributions have been implemented. As shown through three complementary statistical tests, the fitting technique was very satisfactory. A wind resource analysis at 10 m above ground level (AGL) has led to a mean power density at Bujumbura which is almost thirteen fold higher than at Muyinga. The use of the empirical power law to extrapolate wind characteristics at heights from 150 to 350 m AGL has shown that energy potential of hilltops around Muyinga was only suitable for small, individual scale wind energy applications. At the opposite, wind energy potential of ridge-tops and hilltops around Bujumbura has been found suitable for medium and large scale electricity production. For that locality and at those heights, energy outputs and capacity factors (CF or Cf) have been computed for ten selected wind turbines (WTs), together with costs of electricity (COE) using the present value of cost (PVC) method. Amongst those WTs, YDF-1500-87 and S95-2.1 MW have emerged as the best options for installation owing to their highest CF and lowest COE. Moreover, an analysis of those two quantities at monthly basis for YDF-1500-87 WT has led to its best performance in the dry season. Compared to the average present COE of household hydroelectricity consumption, results of this study have evidenced economical feasibility and benefit of WECS setting in selected Burundian sites in order to supplement traditional electricity sources.