The study projects a flexible and compact wearable pear-shaped Super High Frequency(SHF)antenna that can provide detailed location recognition and tracking applicable to defense beacon technology.This mini aperture wi...The study projects a flexible and compact wearable pear-shaped Super High Frequency(SHF)antenna that can provide detailed location recognition and tracking applicable to defense beacon technology.This mini aperture with electrical dimensions of 0.12λ_(0)×0.22λ_(0)×0.01λ_(0)attains a vast bandwidth over 3.1-34.5 GHz Super High Frequency(SHF)frequency band at S_(11)≤-10 dB,peak gain of 7.14 dBi and proportionately homogeneous radiation pattern.The fractional bandwidth(%BW)acquired is 168%that envelopes diversified frequency spectrum inclusive of X band specifically targeted to all kinds of defense and military operations.The proposed antenna can be worn on a soldier's uniform and hence the Specific Absorption Rate simulation is accomplished.The Peak SAR Value over 1 g of tissue is 1.48 W/kg and for 10 g of tissue is 0.27 W/kg well under the safety standards.The flexibility is proven by analyzing the full electromagnetic simulations for various bending conditions.Time response analysis is attained with its Fidelity Factor and Group Delay.Communication excellence is determined using Link Budget Analysis and it is seen that margin at 100 Mbps is 62 m and at 200 Mbps is 59 m.Prototype is fabricated along with experimental validation.All the results show harmony in shaping the antenna to provide critical situational awareness and data sharing capabilities required in defense beacon technology for location identification.展开更多
To study the non-linear fracture, a non-linear constitutive model for piezoelectric ceramics was proposed, in which the polarization switching and saturation were taken into account. Based on the model, the non-linear...To study the non-linear fracture, a non-linear constitutive model for piezoelectric ceramics was proposed, in which the polarization switching and saturation were taken into account. Based on the model, the non-linear fracture analysis was implemented using reproducing kernel particle method （RKPM）. Using local J-integral as a fracture criterion, a relation curve of fracture loads against electric fields was obtained. Qualitatively, the curve is in agreement with the experimental observations reported in literature. The reproducing equation, the shape function of RKPM, and the transformation method to impose essential boundary conditions for meshless methods were also introduced. The computation was implemented using object-oriented programming method.展开更多
The main objective of this paper is to select the optimal model of a hybrid renewable-energy microgrid(MG)system for a village in India.The MG comprises solar photovoltaic(PV)modules,a wind turbine generator,a biomass...The main objective of this paper is to select the optimal model of a hybrid renewable-energy microgrid(MG)system for a village in India.The MG comprises solar photovoltaic(PV)modules,a wind turbine generator,a biomass generator,a battery bank,a diesel generator and an electric vehicle.The optimal model selection is based on technical,economic,environmental,social and reliability parameters.A novel spoonbill swarm optimization algorithm is proposed to select the best hybrid MG system.The optimization results are compared with particle swarm optimization,the genetic algorithm and the grasshopper optimization algorithm.The number or size of components of the optimized MG system is 215 PV modules,92 kW of wind turbine generation,25 kW of biomass generation,267 batteries,22 kW of electric vehicles and 30 kW of diesel generation.The optimized system was selected based on technical factors such as renewable dispersion(93.5%),the duty factor(5.85)and excess energy(15975 kWh/year)as well as eco-nomic considerations including the net present cost(Rs.34686622)and the cost of energy(9.3 Rs./kWh).Furthermore,environ-mental factors such as carbon emissions(396348 kg/year)and atmospheric particulate matter(22.686 kg/year);social factors such as the human progress index(0.68411),the employment generation factor(0.0389)and local employment generation(15.64643);and reliability parameters including loss of power supply probability(0.01%)and availability index(99.99%)were considered during the selection process.The spoonbill swarm optimization algorithm has reduced the convergence time by 1.2 times and decreased the number of iterations by 0.83 times compared with other algorithms.The performance of the MG system is validated in the MATLAB®environment.The results show that the MG system is the optimal system considering technical,economic,environmental,social and reliability parameters.Additionally,the spoonbill swarm optimization algorithm is found to be more efficient than the other algo-rithms in terms of iteration time and convergence time.展开更多
基金the Defense Institute of Advanced Technology,Pune(DIAT,Pune)IIT Delhi。
文摘The study projects a flexible and compact wearable pear-shaped Super High Frequency(SHF)antenna that can provide detailed location recognition and tracking applicable to defense beacon technology.This mini aperture with electrical dimensions of 0.12λ_(0)×0.22λ_(0)×0.01λ_(0)attains a vast bandwidth over 3.1-34.5 GHz Super High Frequency(SHF)frequency band at S_(11)≤-10 dB,peak gain of 7.14 dBi and proportionately homogeneous radiation pattern.The fractional bandwidth(%BW)acquired is 168%that envelopes diversified frequency spectrum inclusive of X band specifically targeted to all kinds of defense and military operations.The proposed antenna can be worn on a soldier's uniform and hence the Specific Absorption Rate simulation is accomplished.The Peak SAR Value over 1 g of tissue is 1.48 W/kg and for 10 g of tissue is 0.27 W/kg well under the safety standards.The flexibility is proven by analyzing the full electromagnetic simulations for various bending conditions.Time response analysis is attained with its Fidelity Factor and Group Delay.Communication excellence is determined using Link Budget Analysis and it is seen that margin at 100 Mbps is 62 m and at 200 Mbps is 59 m.Prototype is fabricated along with experimental validation.All the results show harmony in shaping the antenna to provide critical situational awareness and data sharing capabilities required in defense beacon technology for location identification.
基金Foundation of Southwest Jiaotong Univer-sity (No.2005B25)
文摘To study the non-linear fracture, a non-linear constitutive model for piezoelectric ceramics was proposed, in which the polarization switching and saturation were taken into account. Based on the model, the non-linear fracture analysis was implemented using reproducing kernel particle method （RKPM）. Using local J-integral as a fracture criterion, a relation curve of fracture loads against electric fields was obtained. Qualitatively, the curve is in agreement with the experimental observations reported in literature. The reproducing equation, the shape function of RKPM, and the transformation method to impose essential boundary conditions for meshless methods were also introduced. The computation was implemented using object-oriented programming method.
文摘The main objective of this paper is to select the optimal model of a hybrid renewable-energy microgrid(MG)system for a village in India.The MG comprises solar photovoltaic(PV)modules,a wind turbine generator,a biomass generator,a battery bank,a diesel generator and an electric vehicle.The optimal model selection is based on technical,economic,environmental,social and reliability parameters.A novel spoonbill swarm optimization algorithm is proposed to select the best hybrid MG system.The optimization results are compared with particle swarm optimization,the genetic algorithm and the grasshopper optimization algorithm.The number or size of components of the optimized MG system is 215 PV modules,92 kW of wind turbine generation,25 kW of biomass generation,267 batteries,22 kW of electric vehicles and 30 kW of diesel generation.The optimized system was selected based on technical factors such as renewable dispersion(93.5%),the duty factor(5.85)and excess energy(15975 kWh/year)as well as eco-nomic considerations including the net present cost(Rs.34686622)and the cost of energy(9.3 Rs./kWh).Furthermore,environ-mental factors such as carbon emissions(396348 kg/year)and atmospheric particulate matter(22.686 kg/year);social factors such as the human progress index(0.68411),the employment generation factor(0.0389)and local employment generation(15.64643);and reliability parameters including loss of power supply probability(0.01%)and availability index(99.99%)were considered during the selection process.The spoonbill swarm optimization algorithm has reduced the convergence time by 1.2 times and decreased the number of iterations by 0.83 times compared with other algorithms.The performance of the MG system is validated in the MATLAB®environment.The results show that the MG system is the optimal system considering technical,economic,environmental,social and reliability parameters.Additionally,the spoonbill swarm optimization algorithm is found to be more efficient than the other algo-rithms in terms of iteration time and convergence time.
