A new guidance law, called biased retro proportional navigation(BRPN), is proposed. The guidance law is designed to intercept high-speed targets with angular constraint, which can be used for ballistic target intercep...A new guidance law, called biased retro proportional navigation(BRPN), is proposed. The guidance law is designed to intercept high-speed targets with angular constraint, which can be used for ballistic target interception. BRPN guidance law is defined, and the exact time-varying bias for a required impact angle is derived. Furthermore, the simulation results(trajectory, variation of navigation ratio, capture region, etc) are compared with those of biased proportional navigation(BPN), proportional navigation and retro-proportional navigation. The results show that,at the cost of a higher intercept time, BRPN demands lower terminal lateral acceleration and has larger capture region compared to BPN.展开更多
A new proportional navigation(PN) guidance law,called combined proportional navigation(CPN),is proposed.The guidance law is designed to intercept high-speed targets,which is a common case for ballistic targets.The ran...A new proportional navigation(PN) guidance law,called combined proportional navigation(CPN),is proposed.The guidance law is designed to intercept high-speed targets,which is a common case for ballistic targets.The range of target-to-interceptor speed ratio during target interception is derived when guidance laws are applied in high-speed targets interception,and the effectiveness of negative navigation ratio in the PN-based guidance law is proven analytically in some lemmas.Based on the lemmas,the lateral acceleration command of CPN is defined,and the solution to the appearance of singularity in time-varying navigation ratio is given.The simulation results show that CPN can determine headon engagement(as PN) or tail-chase engagement(as RPN) through initial path angle compared with PN and retro proportional navigation(RPN),and can adjust the value of navigation ratio for head-on engagement or tail-chase engagement.Therefore,the capture region of CPN is larger than that of other guidance laws using PN-based methods.展开更多
Following China and the United States,India is the third highest CO_(2)emitter in the world.With its fast rising population and an industry primarily reliant on coal and oil,the country's emissions will continue t...Following China and the United States,India is the third highest CO_(2)emitter in the world.With its fast rising population and an industry primarily reliant on coal and oil,the country's emissions will continue to rise unless appropriate measures are taken.In India generally the carbon sequestration is done by storing CO_(2)in sedimentary basins where it gets capped by the impermeable cap rocks.The study aims to unfold the other techniques of carbon sequestration in subsurface formations,except for narrating the different types of carbon capture and sequestration techniques along with its storage in different types of environments.For instance,abiotic and biotic environments for CO_(2)sequestration.It further talks about carbon injections of oceanic,geological,and terrestrial types,to name just a few.Types of carbon emission sources are discussed too.In this paper three different approaches are described for carbon mitigation,namely CarbFix,CO_(2)Plume technology and Carbon Trading.A prefeasibility study was done in order to implement the three techniques in Dholera geothermal region in Gujarat,India.In literature review,it can be seen how the three techniques can help in permanent mitigation of captured carbon through carbonate mineralization,power generation and industrial applications.For any project government and public participation is important.In this regard the study gives a brief understanding about the steps to be taken by government and the public to promote such projects for carbon mitigation.Besides,the steps to be taken in such projects for health and risk assessment were talked about in literature review too.展开更多
The capturability of the Three-Dimensional(3D)Realistic True Proportional Navigation(RTPN)guidance law is thoroughly analyzed.The true-arbitrarily maneuvering target is considered,which maneuvers along an arbitrary di...The capturability of the Three-Dimensional(3D)Realistic True Proportional Navigation(RTPN)guidance law is thoroughly analyzed.The true-arbitrarily maneuvering target is considered,which maneuvers along an arbitrary direction in 3D space with an arbitrary but upperbounded acceleration.The whole nonlinear relative kinematics between the interceptor and target is taken into account.First,the upper-bound of commanded acceleration of 3D RTPN is deduced,using a novel Lyapunov-like approach.Second,the reasonable selection range of navigation gain of3D RTPN is analyzed,when the maneuver limitation of interceptor is considered.After that,a more realistic definition of capture is adopted,i.e.,the relative range is smaller than an acceptable miss-distance while the approaching speed is larger than a required impact speed.Unlike previous researches which present Two-Dimensional(2D)capture regions,the inequality analysis technique is utilized to obtain the 3D capture region,where the three coordinates are the closing speed,transversal relative speed,and relative range.The obtained capture region could be taken as a sufficient-but-unnecessary condition of capture.The new theoretical findings are all given in explicit expressions and are more general than previous results.展开更多
文摘A new guidance law, called biased retro proportional navigation(BRPN), is proposed. The guidance law is designed to intercept high-speed targets with angular constraint, which can be used for ballistic target interception. BRPN guidance law is defined, and the exact time-varying bias for a required impact angle is derived. Furthermore, the simulation results(trajectory, variation of navigation ratio, capture region, etc) are compared with those of biased proportional navigation(BPN), proportional navigation and retro-proportional navigation. The results show that,at the cost of a higher intercept time, BRPN demands lower terminal lateral acceleration and has larger capture region compared to BPN.
文摘A new proportional navigation(PN) guidance law,called combined proportional navigation(CPN),is proposed.The guidance law is designed to intercept high-speed targets,which is a common case for ballistic targets.The range of target-to-interceptor speed ratio during target interception is derived when guidance laws are applied in high-speed targets interception,and the effectiveness of negative navigation ratio in the PN-based guidance law is proven analytically in some lemmas.Based on the lemmas,the lateral acceleration command of CPN is defined,and the solution to the appearance of singularity in time-varying navigation ratio is given.The simulation results show that CPN can determine headon engagement(as PN) or tail-chase engagement(as RPN) through initial path angle compared with PN and retro proportional navigation(RPN),and can adjust the value of navigation ratio for head-on engagement or tail-chase engagement.Therefore,the capture region of CPN is larger than that of other guidance laws using PN-based methods.
文摘Following China and the United States,India is the third highest CO_(2)emitter in the world.With its fast rising population and an industry primarily reliant on coal and oil,the country's emissions will continue to rise unless appropriate measures are taken.In India generally the carbon sequestration is done by storing CO_(2)in sedimentary basins where it gets capped by the impermeable cap rocks.The study aims to unfold the other techniques of carbon sequestration in subsurface formations,except for narrating the different types of carbon capture and sequestration techniques along with its storage in different types of environments.For instance,abiotic and biotic environments for CO_(2)sequestration.It further talks about carbon injections of oceanic,geological,and terrestrial types,to name just a few.Types of carbon emission sources are discussed too.In this paper three different approaches are described for carbon mitigation,namely CarbFix,CO_(2)Plume technology and Carbon Trading.A prefeasibility study was done in order to implement the three techniques in Dholera geothermal region in Gujarat,India.In literature review,it can be seen how the three techniques can help in permanent mitigation of captured carbon through carbonate mineralization,power generation and industrial applications.For any project government and public participation is important.In this regard the study gives a brief understanding about the steps to be taken by government and the public to promote such projects for carbon mitigation.Besides,the steps to be taken in such projects for health and risk assessment were talked about in literature review too.
基金supported in part by the National Natural Science Foundation of China(No.12002370)in part by the Hunan Provincial Natural Science Foundation of China(No.2019JJ50736)。
文摘The capturability of the Three-Dimensional(3D)Realistic True Proportional Navigation(RTPN)guidance law is thoroughly analyzed.The true-arbitrarily maneuvering target is considered,which maneuvers along an arbitrary direction in 3D space with an arbitrary but upperbounded acceleration.The whole nonlinear relative kinematics between the interceptor and target is taken into account.First,the upper-bound of commanded acceleration of 3D RTPN is deduced,using a novel Lyapunov-like approach.Second,the reasonable selection range of navigation gain of3D RTPN is analyzed,when the maneuver limitation of interceptor is considered.After that,a more realistic definition of capture is adopted,i.e.,the relative range is smaller than an acceptable miss-distance while the approaching speed is larger than a required impact speed.Unlike previous researches which present Two-Dimensional(2D)capture regions,the inequality analysis technique is utilized to obtain the 3D capture region,where the three coordinates are the closing speed,transversal relative speed,and relative range.The obtained capture region could be taken as a sufficient-but-unnecessary condition of capture.The new theoretical findings are all given in explicit expressions and are more general than previous results.
