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Attention to intercropping for sustainable agriculture is increasing, and scientific studies on intercropping have also grown in recent years. Agroforestry Systems, which combine annual crops with trees, are used widely in semiarid regions to reduce wind erosion and improve the efficiency of resources such as water and nutrients. Field experiments were conducted at Tamil Nadu Newsprint and Papers Limited Farm, Mondipatty, Tamil Nadu, to study the compatibility of intercropping systems in the Dalbergia sissoo-based Horti-silvicultural system for two years during 2016 and 2017. The experiments were conducted in a split-plot design with four replications.The main plot treatments were M1: Cassava M2:Chillies and the subplot treatments were five nutrient management packages viz., S1: Untreated control, S2: 100 % Recommended Dose of Fertilizers (Cassava: 90: 90: 240 and Chillies: 60: 80: 80),S3: 125 % Recommended Dose of Fertilizers (Cassava: 112.5: 112.5: 300 and Chillies: 75: 100: 100), S4:150 % (Cassava: 135: 135: 360 and Chillies: 90: 120: 120) Recommended Dose of Fertilizers, S5: Soil Test Crop Response studies - Integrated Plant Nutrient Supply System -based recommendation (as per soil test value). The results indicated that the Horti-Silvicultural system of growing Cassava and Chillies along with D. sissoo performed well. It was observed that statistically significant (p ≤ 0.05) higher yields of 17.8 tha-1 and 1.6 tha-1 were recorded in Cassava and Chillies, respectively, in treatment S5, where the fertilizer was applied based on the Soil Test Crop Response studies - Integrated Plant Nutrient Supply System. In addition, the soil fertility status was also sustained in this plot. The fertilizers applied to the intercrops have contributed to the nutrient requirement of the tree crop and thereby reduced the cost of cultivation in the agroforestry system.

In pole-phase modulation the phase order is coming down by pole ratio times in high pole mode, which results in the higher magnitude of spatial harmonics as well as higher torque ripple. Hence, for minimizing torque ripple, in this paper, the available three identical voltage fed windings per effective phase in 3-phase 12-pole (3PH-12PO) mode are used to develop the simple multilevel inverter (MLI) configuration. The proposed MLI scheme is realized with three 5-leg inverter modules. Each 5 leg inverter module will generate 3 level voltage across the phase, thereby resultant voltage seen by each phase winding is 5 level voltage in 3PH-12PO mode. This multilevel voltage will improve the torque ripple profile of the motor drive. In addition, the proposed MLI scheme along with phase grouping will enrich the linear modulation range of the Pole Phase Modulated Induction Motor (PPMIM) drive in 9-phase 4-pole (9PH-4PO) mode. The switches used to generate multilevel voltage in 3PH-12PO mode are effectively utilized for blocking the flow of circulating currents. As compared to other conventional 9-phase 5-level inverters the proposed 5-level inverter requires only 30 switches and it doesn't require extra clamping diodes/capacitors and extra bidirectional switches for isolating neutrals in 9PH-4PO operation.

In pole-phase modulation the phase order is coming down by pole ratio times in high pole mode, which results in the higher magnitude of spatial harmonics as well as higher torque ripple. Hence, for minimizing torque ripple, in this paper, the available three identical voltage fed windings per effective phase in 3-phase 12-pole (3PH-12PO) mode are used to develop the simple multilevel inverter (MLI) configuration. The proposed MLI scheme is realized with three 5-leg inverter modules. Each 5 leg inverter module will generate 3 level voltage across the phase, thereby resultant voltage seen by each phase winding is 5 level voltage in 3PH-12PO mode. This multilevel voltage will improve the torque ripple profile of the motor drive. In addition, the proposed MLI scheme along with phase grouping will enrich the linear modulation range of the Pole Phase Modulated Induction Motor (PPMIM) drive in 9-phase 4-pole (9PH-4PO) mode. The switches used to generate multilevel voltage in 3PH-12PO mode are effectively utilized for blocking the flow of circulating currents. As compared to other conventional 9-phase 5-level inverters the proposed 5-level inverter requires only 30 switches and it doesn't require extra clamping diodes/capacitors and extra bidirectional switches for isolating neutrals in 9PH-4PO operation.

In pole-phase modulation the phase order is coming down by pole ratio times in high pole mode, which results in the higher magnitude of spatial harmonics as well as higher torque ripple. Hence, for minimizing torque ripple, in this paper, the available three identical voltage fed windings per effective phase in 3-phase 12-pole (3PH-12PO) mode are used to develop the simple multilevel inverter (MLI) configuration. The proposed MLI scheme is realized with three 5-leg inverter modules. Each 5 leg inverter module will generate 3 level voltage across the phase, thereby resultant voltage seen by each phase winding is 5 level voltage in 3PH-12PO mode. This multilevel voltage will improve the torque ripple profile of the motor drive. In addition, the proposed MLI scheme along with phase grouping will enrich the linear modulation range of the Pole Phase Modulated Induction Motor (PPMIM) drive in 9-phase 4-pole (9PH-4PO) mode. The switches used to generate multilevel voltage in 3PH-12PO mode are effectively utilized for blocking the flow of circulating currents. As compared to other conventional 9-phase 5-level inverters the proposed 5-level inverter requires only 30 switches and it doesn't require extra clamping diodes/capacitors and extra bidirectional switches for isolating neutrals in 9PH-4PO operation.

In multiphase induction motors the number of slots per pole per phase comes down due to the higher number of phases, which results the airgap MMF per phase closer to square wave. In addition, as the number of poles increases the space harmonics will increase further in Pole-phase modulated induction motor drives (PPMIM) drives. To address this issues, in this paper a distributed short pitch winding (DSPW) is proposed for PPMIM drives. In DSPW, the number of conductors per phase are distributed over three stator slots that will generate the multi-stepped MMF wave in airgap as compared to concentrated winding. Because of this, the space harmonics in the airgap as well as the harmonics in induced EMF will come down, which improves the performance of the drive. The PPMIM drive with proposed DSPW, is capable to operate in 9-phase 2-pole mode and 3-phase 6-pole mode without changing the stator winding connections. A 5hp, nine-phase PPMIM drive with the proposed DSPW is designed by using Ansys Maxwell 2-D FEM tool. The power circuit is designed in Simplorer environment (associated tool for Maxwell 2-D) for co-simulating the Maxwell model of PPMIM drive. Moreover, the torque ripple percentage of PPMIM drive for both concentrated winding as well as for distributed winding has been compared. The proposed drive will offer the wider range of speed and torques which is best suitable for traction and ship propulsion applications.

In multiphase induction motors the number of slots per pole per phase comes down due to the higher number of phases, which results the airgap MMF per phase closer to square wave. In addition, as the number of poles increases the space harmonics will increase further in Pole-phase modulated induction motor drives (PPMIM) drives. To address this issues, in this paper a distributed short pitch winding (DSPW) is proposed for PPMIM drives. In DSPW, the number of conductors per phase are distributed over three stator slots that will generate the multi-stepped MMF wave in airgap as compared to concentrated winding. Because of this, the space harmonics in the airgap as well as the harmonics in induced EMF will come down, which improves the performance of the drive. The PPMIM drive with proposed DSPW, is capable to operate in 9-phase 2-pole mode and 3-phase 6-pole mode without changing the stator winding connections. A 5hp, nine-phase PPMIM drive with the proposed DSPW is designed by using Ansys Maxwell 2-D FEM tool. The power circuit is designed in Simplorer environment (associated tool for Maxwell 2-D) for co-simulating the Maxwell model of PPMIM drive. Moreover, the torque ripple percentage of PPMIM drive for both concentrated winding as well as for distributed winding has been compared. The proposed drive will offer the wider range of speed and torques which is best suitable for traction and ship propulsion applications.

In multiphase induction motors the number of slots per pole per phase comes down due to the higher number of phases, which results the airgap MMF per phase closer to square wave. In addition, as the number of poles increases the space harmonics will increase further in Pole-phase modulated induction motor drives (PPMIM) drives. To address this issues, in this paper a distributed short pitch winding (DSPW) is proposed for PPMIM drives. In DSPW, the number of conductors per phase are distributed over three stator slots that will generate the multi-stepped MMF wave in airgap as compared to concentrated winding. Because of this, the space harmonics in the airgap as well as the harmonics in induced EMF will come down, which improves the performance of the drive. The PPMIM drive with proposed DSPW, is capable to operate in 9-phase 2-pole mode and 3-phase 6-pole mode without changing the stator winding connections. A 5hp, nine-phase PPMIM drive with the proposed DSPW is designed by using Ansys Maxwell 2-D FEM tool. The power circuit is designed in Simplorer environment (associated tool for Maxwell 2-D) for co-simulating the Maxwell model of PPMIM drive. Moreover, the torque ripple percentage of PPMIM drive for both concentrated winding as well as for distributed winding has been compared. The proposed drive will offer the wider range of speed and torques which is best suitable for traction and ship propulsion applications.

A multilevel inverter topology for a four-pole induction-motor drive is presented in this paper, which is constructed using the induction-motor stator winding arrangement. A single dc source with a less magnitude when compared with conventional five-level inverter topologies is used in this topology. Therefore, power balancing issues (which are major challenges in conventional multilevel inverters) are minimized. As this configuration uses a single dc source, it provides a path for zero-sequence currents because of the zero-sequence voltages present in the output, which will flow through the motor phase winding and power electronic switches. To minimize these zero-sequence currents, sine-triangle pulsewidth modulation (SPWM) is used, which will shift the lower order harmonics near to switching frequency in the linear modulation region. However, in the case of overmodulation, harmonic voltages will be introduced close to the fundamental frequency. In this regard, a modified SPWM technique is proposed in this paper to operate the drive in the overmodulation region up to the modulation index of 2/surd{3}. The proposed quad two-level inverter topology is experimentally verified with a laboratory prototype on a four-pole 5-hp induction motor. Experimental results show the effectiveness of the proposed topology in the complete linear modulation region and the overmodulation region.

A multilevel inverter topology for a four-pole induction-motor drive is presented in this paper, which is constructed using the induction-motor stator winding arrangement. A single dc source with a less magnitude when compared with conventional five-level inverter topologies is used in this topology. Therefore, power balancing issues (which are major challenges in conventional multilevel inverters) are minimized. As this configuration uses a single dc source, it provides a path for zero-sequence currents because of the zero-sequence voltages present in the output, which will flow through the motor phase winding and power electronic switches. To minimize these zero-sequence currents, sine-triangle pulsewidth modulation (SPWM) is used, which will shift the lower order harmonics near to switching frequency in the linear modulation region. However, in the case of overmodulation, harmonic voltages will be introduced close to the fundamental frequency. In this regard, a modified SPWM technique is proposed in this paper to operate the drive in the overmodulation region up to the modulation index of 2/surd{3}. The proposed quad two-level inverter topology is experimentally verified with a laboratory prototype on a four-pole 5-hp induction motor. Experimental results show the effectiveness of the proposed topology in the complete linear modulation region and the overmodulation region.

A multilevel inverter topology for a four-pole induction-motor drive is presented in this paper, which is constructed using the induction-motor stator winding arrangement. A single dc source with a less magnitude when compared with conventional five-level inverter topologies is used in this topology. Therefore, power balancing issues (which are major challenges in conventional multilevel inverters) are minimized. As this configuration uses a single dc source, it provides a path for zero-sequence currents because of the zero-sequence voltages present in the output, which will flow through the motor phase winding and power electronic switches. To minimize these zero-sequence currents, sine-triangle pulsewidth modulation (SPWM) is used, which will shift the lower order harmonics near to switching frequency in the linear modulation region. However, in the case of overmodulation, harmonic voltages will be introduced close to the fundamental frequency. In this regard, a modified SPWM technique is proposed in this paper to operate the drive in the overmodulation region up to the modulation index of 2/surd{3}. The proposed quad two-level inverter topology is experimentally verified with a laboratory prototype on a four-pole 5-hp induction motor. Experimental results show the effectiveness of the proposed topology in the complete linear modulation region and the overmodulation region.

A multilevel inverter topology for a four-pole induction-motor drive is presented in this paper, which is constructed using the induction-motor stator winding arrangement. A single dc source with a less magnitude when compared with conventional five-level inverter topologies is used in this topology. Therefore, power balancing issues (which are major challenges in conventional multilevel inverters) are minimized. As this configuration uses a single dc source, it provides a path for zero-sequence currents because of the zero-sequence voltages present in the output, which will flow through the motor phase winding and power electronic switches. To minimize these zero-sequence currents, sine-triangle pulsewidth modulation (SPWM) is used, which will shift the lower order harmonics near to switching frequency in the linear modulation region. However, in the case of overmodulation, harmonic voltages will be introduced close to the fundamental frequency. In this regard, a modified SPWM technique is proposed in this paper to operate the drive in the overmodulation region up to the modulation index of 2/surd{3}. The proposed quad two-level inverter topology is experimentally verified with a laboratory prototype on a four-pole 5-hp induction motor. Experimental results show the effectiveness of the proposed topology in the complete linear modulation region and the overmodulation region.

Problem statement: The present work was attempted to evaluate the probiotic activity of Bacillus spp. in shrimp health management. Approach: Penaeid culture ecosystem as a confined environment with huge inputs always encourages the proliferation of pathogenic bacteria like Vibrios. Results: From the present study and earlier reports it is understood that these pathogens alone or combine with virus especially White Spot Syndrome Virus (WSSV) lead to sudden disease outbreaks and mortality. However the unwarranted and unwanted usage of antibiotics causes negative impacts rather than controlling diseases. Conclusion: Based on this, it is concluded that application of suitable and effective probiotics (Bacillus) will certainly reduce population of pathogens and provide a congenial pond environment for shrimp culture. However, this could be achieved by the effective usage of commercially available probiotics for maintaining good pond environment.

Problem statement: The present work was attempted to evaluate the probiotic activity of Bacillus spp. in shrimp health management. Approach: Penaeid culture ecosystem as a confined environment with huge inputs always encourages the proliferation of pathogenic bacteria like Vibrios. Results: From the present study and earlier reports it is understood that these pathogens alone or combine with virus especially White Spot Syndrome Virus (WSSV) lead to sudden disease outbreaks and mortality. However the unwarranted and unwanted usage of antibiotics causes negative impacts rather than controlling diseases. Conclusion: Based on this, it is concluded that application of suitable and effective probiotics (Bacillus) will certainly reduce population of pathogens and provide a congenial pond environment for shrimp culture. However, this could be achieved by the effective usage of commercially available probiotics for maintaining good pond environment.