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In most of the applications involving three-phase machines, speed control of the machine plays an important role. For the speed control the most popular method used is the v/f method. The v/f method aims at maintaining the flux constant by varying voltage and frequency proportionately. But the v/f method has its own share of drawbacks. One of the major disadvantage of v/f method is the inferior dynamic performance. In order to overcome the disadvantages of the v/f method one of the best solution is preferring multiphase systems in spite of the conventional three-phase systems. In multiphase systems the effect of harmonics on the main flux is reduced in-turn reducing the pulsating torques. In this paper the v/f control of a threephase Induction motor is implemented and the results are analysed. A comparison is made between the three-phase and five-phase inverters with different PWM techniques. The inverters are modelled using MATLAB/SIMULINK, the results are compared and analysed. In this paper the %THD in phase voltages obtained from the three PWM technique applied for both three-phase and five-phase inverters is calculated and compared.

Assessment of above ground forest biomass (AGB) is essential in carbon modelling studies to provide mitigation strategies as demonstrated by reducing emissions from deforestation and forest degradation. Several researchers have demonstrated the use of remote sensing data in spatial AGB estimation, in terms of spectral and radar backscatter based approaches at a landscape scale with several known limitations. However, these methods lacked the predictive ability at high biomass ranges due to saturation. The current study addresses the problem of saturation at high biomass ranges using canopy textural metric from high resolution optical data. Fourier transform based textural ordination (FOTO) technique, which involves deriving radial spectrum information via 2D fast Fourier transform and ordination through principal component analysis was used for characterizing the textural properties of forest canopies. In the current study, plot level estimated AGB from 15 (1 ha) plots was used to relate with texture derived information from very high resolution datasets (viz., IKONOS and Cartosat-1). In addition to the estimation of high biomass ranges, one of the prime objective of the current study is to understand the effects of spatial resolution on deriving textural-AGB relationship from 2.5 m IRS Cartosat data (Cartosat-A, viewing angle = -5A degrees) to that of IKONOS imagery with near nadir view. Further, since texture is impacted by several illumination geometry issues, the effect of viewing geometry on the relationship was evaluated using Cartosat-F (Viewing angle = 26A degrees) imagery. The results show that the FOTO method using stereo Cartosat (A and F) images at 2.5 m resolution are able to perform well in characterizing high AGB values since the texture-biomass relationship is only subjected to 18 % relative error to that of 15 % in case of IKONOS and could aid in reduction of uncertainty in AGB estimation at a large landscape levels.

Chief executive officers play a vital role in the strategic initiatives regarding R&D and innovation, and to ensure strategic fit. In the globalised environment, focus on research and development is more important to gain competitive advantage. Hence, this work is carried out to understand and explore the influence of CEO on the strategic orientation in Indian public sector units. An empirical study was conducted, using research instrument designed to survey CEOs, in public sector units. Data collected from 74 public sector units were analysed using multiple regression and correlation. The analysis indicated that CEO characteristics, job attitude, and focus towards R&D influence the formulation of R&D vision in Indian PSUs, weakly. In addition, the study also revealed various other factors of importance that must have been the major concerns for the sickness of many public sector units. The study unveils the probable reasons for lack of growth in the sector.

Public sector organisations in India were established after the independence to build infrastructure for economic development, generate employment and various other reasons. Since the liberalisation of the economy in 1991, the mortality rate of public sector units (PSUs) has been found to be on the rise. This dynamics has been captured using soft systems methodology. A system dynamics model representing the operational and performance dynamics of Indian PSUs in the era of transformation from the preglobalisation through globalisation and post-globalisation periods was developed. Policy experimentation reveals that chief executive officers with strategic orientation towards research and development improve revenue generations. Furthermore, it revealed that Indian PSUs would have earned more revenues had there not been globalisation.