Detecting the environment around the supermassive black holes and tests of general relativity are important applications of extreme-mass-ratio inspirals(EMRIs).There is still a challenge to efficiently describe variou...Detecting the environment around the supermassive black holes and tests of general relativity are important applications of extreme-mass-ratio inspirals(EMRIs).There is still a challenge to efficiently describe various“dirty”impacts on the inspirals,such as dark matter,gas,dipole radiation,and electromagnetic interaction.In this study,we find the inherent linearity of the asymptotic solution of the inhomogeneous Teukolsky equation.On the basis of this property,we completely decouple the factors of the perturber and the background spacetime in the energy fluxes and waveforms.With the new decoupling form,the waveforms of EMRIs with non-geodesic motion in Kerr spacetime can be conveniently calculated.This will help to resolve the environment(including gas,field,dark matter,electromagnetic interaction)around supermassive black holes and test general relativity.展开更多
Extreme-mass-ratio inspirals(EMRIs)are among the most important sources for future spaceborne gravitational wave detectors.In this kind of system,compact objects usually orbit around central supermassive black holes o...Extreme-mass-ratio inspirals(EMRIs)are among the most important sources for future spaceborne gravitational wave detectors.In this kind of system,compact objects usually orbit around central supermassive black holes on complicated trajectories.Usually,these trajectories are approximated as the geodesics of Kerr space-times,and orbital evolution is simulated with the help of the adiabatic approximation.However,this approach omits the influence of the compact object on its background.In this paper,using the effective one-body formalism,we analytically calculate the trajectory of a nonspinning compact object around a massive Kerr black hole in an equatorial eccentric orbit(omitting the orbital inclination)and express the fundamental orbital frequencies in explicit forms.Our formalism includes the first-order corrections for the mass ratio in the conservative orbital motion.Furthermore,we insert the mass-ratio-related terms into the first post-Newtonian energy fluxes.By calculating the gravitational waves using the Teukolsky equations,we quantitatively reveal the influence of the mass of the compact object on the data analysis.We find that the shrinking of geodesic motion by taking small objects as test particles may not be appropriate for the detection of EMRIs.展开更多
The binocular stereo vision is the lowest cost sensor for obtaining 3D information.Considering the weakness of long‐distance measurement and stability,the improvement of accuracy and stability of stereo vision is urg...The binocular stereo vision is the lowest cost sensor for obtaining 3D information.Considering the weakness of long‐distance measurement and stability,the improvement of accuracy and stability of stereo vision is urgently required for application of precision agriculture.To address the challenges of stereo vision long‐distance measurement and stable perception without hardware upgrade,inspired by hawk eyes,higher resolution perception and the adaptive HDR(High Dynamic Range)were introduced in this paper.Simulating the function from physiological structure of‘deep fovea’and‘shallow fovea’of hawk eye,the higher resolution reconstruction method in this paper was aimed at ac-curacy improving.Inspired by adjustment of pupils,the adaptive HDR method was proposed for high dynamic range optimisation and stable perception.In various light conditions,compared with default stereo vision,the accuracy of proposed algorithm was improved by 28.0%evaluated by error ratio,and the stability was improved by 26.56%by disparity accuracy.For fixed distance measurement,the maximum improvement was 78.6%by standard deviation.Based on the hawk‐eye‐inspired perception algorithm,the point cloud of orchard was improved both in quality and quantity.The hawk‐eye‐inspired perception algorithm contributed great advance in binocular 3D point cloud recon-struction in orchard navigation map.展开更多
Masquerade culture is an essential part of Sekondi-Takoradi cultural embodiment. The masquerade festival titled Ankos displays interesting costumes that have artistic elements of potent colour display and performances...Masquerade culture is an essential part of Sekondi-Takoradi cultural embodiment. The masquerade festival titled Ankos displays interesting costumes that have artistic elements of potent colour display and performances. The masquerade costumes manifest intricate fabric decoration techniques for example pleating, folding, gathering, smocking, hand and machine stitching and the use of varied colour schemes. These decorative techniques make costume production laborious, tedious and downtime constraints. In contributing to the innovative approaches to creating textile designs and prints, the study explored the inspirational possibilities of surface designs of the masquerade costume for textile designs and prints. The art-based research design and direct observation as research instrumentation were employed in the artistic creation for the study. Adobe Photoshop was used in the simulation design processes. The study revealed that the simulation design processes produced an innovative imitated visual appearance of the masquerade costume and production processes from a machine-stitched work to a hand-printed fabric. It is recommended that costume makers adopt the contemporary possibility of using hand screen to print hitherto the traditional laborious and tedious process of producing masquerade costumes.展开更多
基金supported by the National Key R&D Program of China(Grant No.2021YFC2203002)the National Natural Science Foundation of China(Grant No.12173071)。
文摘Detecting the environment around the supermassive black holes and tests of general relativity are important applications of extreme-mass-ratio inspirals(EMRIs).There is still a challenge to efficiently describe various“dirty”impacts on the inspirals,such as dark matter,gas,dipole radiation,and electromagnetic interaction.In this study,we find the inherent linearity of the asymptotic solution of the inhomogeneous Teukolsky equation.On the basis of this property,we completely decouple the factors of the perturber and the background spacetime in the energy fluxes and waveforms.With the new decoupling form,the waveforms of EMRIs with non-geodesic motion in Kerr spacetime can be conveniently calculated.This will help to resolve the environment(including gas,field,dark matter,electromagnetic interaction)around supermassive black holes and test general relativity.
基金NSFC No.11773059supported by MEXT,the JSPS Leading-edge Research Infrastructure Program,JSPS Grantin-Aid for Specially Promoted Research 26000005,JSPS Grant-in-Aid for Scientific Research on Innovative Areas 2905:JP17H06358,JP17H06361,and JP17H06364,JSPS Core-to-Core Program A.Advanced Research Networks,JSPS Grant-in-Aid for Scientific Research(S)17H06133,the joint research program of the Institute for Cosmic Ray Research,the University of Tokyothe Key Research Program of Frontier Sciences,CAS,No.QYZDB-SSWSYS016。
文摘Extreme-mass-ratio inspirals(EMRIs)are among the most important sources for future spaceborne gravitational wave detectors.In this kind of system,compact objects usually orbit around central supermassive black holes on complicated trajectories.Usually,these trajectories are approximated as the geodesics of Kerr space-times,and orbital evolution is simulated with the help of the adiabatic approximation.However,this approach omits the influence of the compact object on its background.In this paper,using the effective one-body formalism,we analytically calculate the trajectory of a nonspinning compact object around a massive Kerr black hole in an equatorial eccentric orbit(omitting the orbital inclination)and express the fundamental orbital frequencies in explicit forms.Our formalism includes the first-order corrections for the mass ratio in the conservative orbital motion.Furthermore,we insert the mass-ratio-related terms into the first post-Newtonian energy fluxes.By calculating the gravitational waves using the Teukolsky equations,we quantitatively reveal the influence of the mass of the compact object on the data analysis.We find that the shrinking of geodesic motion by taking small objects as test particles may not be appropriate for the detection of EMRIs.
基金funded by the National Natural Science Foundation of China(No.51979275)Key Laboratory of Spatial‐temporal Big Data Analysis and Application of Nat-ural Resources in Megacities,MNR(No.KFKT‐2022‐05)+3 种基金Open Fund of Key Laboratory of Urban Land Resources Monitoring and Simulation,Ministry of Natural Resources(No.KF‐2021‐06‐115)Open Project Program of State Key Laboratory of Virtual Reality Technology and Systems,Bei-hang University(No.VRLAB2022C10)Jiangsu Province and Education Ministry Co‐sponsored Synergistic Innovation Center of Modern Agricultural Equipment(No.XTCX2002)2115 Talent Development Program of China Agricultural University and Chinese Universities Scientific Fund(No.2021TC105).
文摘The binocular stereo vision is the lowest cost sensor for obtaining 3D information.Considering the weakness of long‐distance measurement and stability,the improvement of accuracy and stability of stereo vision is urgently required for application of precision agriculture.To address the challenges of stereo vision long‐distance measurement and stable perception without hardware upgrade,inspired by hawk eyes,higher resolution perception and the adaptive HDR(High Dynamic Range)were introduced in this paper.Simulating the function from physiological structure of‘deep fovea’and‘shallow fovea’of hawk eye,the higher resolution reconstruction method in this paper was aimed at ac-curacy improving.Inspired by adjustment of pupils,the adaptive HDR method was proposed for high dynamic range optimisation and stable perception.In various light conditions,compared with default stereo vision,the accuracy of proposed algorithm was improved by 28.0%evaluated by error ratio,and the stability was improved by 26.56%by disparity accuracy.For fixed distance measurement,the maximum improvement was 78.6%by standard deviation.Based on the hawk‐eye‐inspired perception algorithm,the point cloud of orchard was improved both in quality and quantity.The hawk‐eye‐inspired perception algorithm contributed great advance in binocular 3D point cloud recon-struction in orchard navigation map.
文摘Masquerade culture is an essential part of Sekondi-Takoradi cultural embodiment. The masquerade festival titled Ankos displays interesting costumes that have artistic elements of potent colour display and performances. The masquerade costumes manifest intricate fabric decoration techniques for example pleating, folding, gathering, smocking, hand and machine stitching and the use of varied colour schemes. These decorative techniques make costume production laborious, tedious and downtime constraints. In contributing to the innovative approaches to creating textile designs and prints, the study explored the inspirational possibilities of surface designs of the masquerade costume for textile designs and prints. The art-based research design and direct observation as research instrumentation were employed in the artistic creation for the study. Adobe Photoshop was used in the simulation design processes. The study revealed that the simulation design processes produced an innovative imitated visual appearance of the masquerade costume and production processes from a machine-stitched work to a hand-printed fabric. It is recommended that costume makers adopt the contemporary possibility of using hand screen to print hitherto the traditional laborious and tedious process of producing masquerade costumes.
