The gravitational wave background(GWB) produced by extreme-mass-ratio inspirals(EMRIs) serves as a powerful tool for probing the astrophysical and dynamical processes in galactic centers. EMRI systems are a primary ta...The gravitational wave background(GWB) produced by extreme-mass-ratio inspirals(EMRIs) serves as a powerful tool for probing the astrophysical and dynamical processes in galactic centers. EMRI systems are a primary target for the space-based detector laser interferometer space antenna due to their long-lived signals and high signal-to-noise ratios. This study explores the statistical properties of the GWB from EMRI, focusing on the calculation methods for the GWB, the astrophysical distribution of EMRI sources, and the influence of key parameters, including the spin of supermassive black holes(SMBHs) and the masses of compact objects(COs). By analyzing these factors, we determine the distribution range of the characteristic strain of the GWB from EMRIs. We find that the final eccentricity distributions appear to have negligible effect on the intensity of the GWB due to rapid circularization before they become detectable and the spin of the SMBH enhances the gravitational wave characteristic strain by approximately 1% compared to cases without spin effects. The masses of COs can also significantly affect the characteristic strain of the GWB from EMRIs, with black hole as CO producing a gravitational wave signal intensity that is approximately one order of magnitude higher compared to cases where neutron star or white dwarf are the COs.展开更多
A probe test method was employed to detect the friction condition of the interfaces between tools and blank. At the same time a self-developed measurement apparatus to realize the probe test method was also presented....A probe test method was employed to detect the friction condition of the interfaces between tools and blank. At the same time a self-developed measurement apparatus to realize the probe test method was also presented. Based on the analysis of force, a correlative friction model was also given. With the self-developed measurement apparatus,the effects of three kinds of lubricating oils which were in common use during the process of sheet steel drawing were studied. By probing the friction coefficient values of different lubricating oils during the drawing process of the hot-galvanized sheet steel (steel brand: ST07Zn), we can see that the friction caused by PK oil was the lowest, so the effect of PK oil was the best. Then PK oil was used as the base lubricating oil and some solid additive powers was added into it to make a new type lubrication (named as L oil).The result of test proved that the new lubricating oil had remarkable effect on the drawing process of hot-galvanized sheet steel.展开更多
The processing of ceramic-probe made by superpure alumina for electric-capacity liquidometer is reported in present paper. The probe which has higher mechanical strength, more chemical stability and better electric in...The processing of ceramic-probe made by superpure alumina for electric-capacity liquidometer is reported in present paper. The probe which has higher mechanical strength, more chemical stability and better electric insulating properties can ensure that the electric-capacity liquidometer works well under the violent vibrational shock. The mechanical and chemical properties and the microstructure of the materials used for the probe are studied.展开更多
The CASTRIP* process produces a range of high strength Ultra-thin Cast Strip (UCS) products (380-550 MPa) in thicknesses between 0.9 mm and 1.5 mm, which is very challenging to produce via conventional hot and cold ro...The CASTRIP* process produces a range of high strength Ultra-thin Cast Strip (UCS) products (380-550 MPa) in thicknesses between 0.9 mm and 1.5 mm, which is very challenging to produce via conventional hot and cold rolled processing routes. The twin roll CASTRIP process fully exploits the hardenability and strengthening potential of Nb in a low C-Mn-Nb-V microalloyed steel type. Significant microstructural strengthening from solute Nb was obtained, even at low microalloying levels, as well as modest Mn additions, through enhancing the hardenability and further strengthening was obtained in coated products by exploiting age hardening during processing on a continuous hot dip galvanising line. Atom probe tomography and TEM determined that Nb was retained in solid solution and subsequent age hardening resulted from the formation of Nb and V rich nanosized particles. Age hardening was achieved without loss of ductility producing galvanised strip with an excellent strength-ductility combination (Y.S. 】600 MPa, T.E. 】10%).展开更多
A 3D probe used for NC\|copying process is proposed in the paper. The construction of parallel springs is adopted in the probe. It has compact structure and little volume. By adjusting spring force and improving sensi...A 3D probe used for NC\|copying process is proposed in the paper. The construction of parallel springs is adopted in the probe. It has compact structure and little volume. By adjusting spring force and improving sensitivity, the probe can be used in CMM. Errors of the probe are analysed. Performances of the probe are verified by test of measuring force, verification of precision of single axis and plane precision.展开更多
Sonar image processing system is an important intelligent system of Autonomous Un-derwater Vehicle.Based on TMS320C30 high speed DSP,it is used to realize sonar imagecompression and underwater object detections includ...Sonar image processing system is an important intelligent system of Autonomous Un-derwater Vehicle.Based on TMS320C30 high speed DSP,it is used to realize sonar imagecompression and underwater object detections including obstacle recognition in real time.Inthis paper,the software and hardware designs of this system are introduced and the experi-mental results are given.展开更多
基金supported by the National Key R&D Program of China (Grant No. 2020YFC2201400)。
文摘The gravitational wave background(GWB) produced by extreme-mass-ratio inspirals(EMRIs) serves as a powerful tool for probing the astrophysical and dynamical processes in galactic centers. EMRI systems are a primary target for the space-based detector laser interferometer space antenna due to their long-lived signals and high signal-to-noise ratios. This study explores the statistical properties of the GWB from EMRI, focusing on the calculation methods for the GWB, the astrophysical distribution of EMRI sources, and the influence of key parameters, including the spin of supermassive black holes(SMBHs) and the masses of compact objects(COs). By analyzing these factors, we determine the distribution range of the characteristic strain of the GWB from EMRIs. We find that the final eccentricity distributions appear to have negligible effect on the intensity of the GWB due to rapid circularization before they become detectable and the spin of the SMBH enhances the gravitational wave characteristic strain by approximately 1% compared to cases without spin effects. The masses of COs can also significantly affect the characteristic strain of the GWB from EMRIs, with black hole as CO producing a gravitational wave signal intensity that is approximately one order of magnitude higher compared to cases where neutron star or white dwarf are the COs.
文摘A probe test method was employed to detect the friction condition of the interfaces between tools and blank. At the same time a self-developed measurement apparatus to realize the probe test method was also presented. Based on the analysis of force, a correlative friction model was also given. With the self-developed measurement apparatus,the effects of three kinds of lubricating oils which were in common use during the process of sheet steel drawing were studied. By probing the friction coefficient values of different lubricating oils during the drawing process of the hot-galvanized sheet steel (steel brand: ST07Zn), we can see that the friction caused by PK oil was the lowest, so the effect of PK oil was the best. Then PK oil was used as the base lubricating oil and some solid additive powers was added into it to make a new type lubrication (named as L oil).The result of test proved that the new lubricating oil had remarkable effect on the drawing process of hot-galvanized sheet steel.
文摘The processing of ceramic-probe made by superpure alumina for electric-capacity liquidometer is reported in present paper. The probe which has higher mechanical strength, more chemical stability and better electric insulating properties can ensure that the electric-capacity liquidometer works well under the violent vibrational shock. The mechanical and chemical properties and the microstructure of the materials used for the probe are studied.
文摘The CASTRIP* process produces a range of high strength Ultra-thin Cast Strip (UCS) products (380-550 MPa) in thicknesses between 0.9 mm and 1.5 mm, which is very challenging to produce via conventional hot and cold rolled processing routes. The twin roll CASTRIP process fully exploits the hardenability and strengthening potential of Nb in a low C-Mn-Nb-V microalloyed steel type. Significant microstructural strengthening from solute Nb was obtained, even at low microalloying levels, as well as modest Mn additions, through enhancing the hardenability and further strengthening was obtained in coated products by exploiting age hardening during processing on a continuous hot dip galvanising line. Atom probe tomography and TEM determined that Nb was retained in solid solution and subsequent age hardening resulted from the formation of Nb and V rich nanosized particles. Age hardening was achieved without loss of ductility producing galvanised strip with an excellent strength-ductility combination (Y.S. 】600 MPa, T.E. 】10%).
基金Supported by the National Natural Science Foundation of China (50175037)
文摘A 3D probe used for NC\|copying process is proposed in the paper. The construction of parallel springs is adopted in the probe. It has compact structure and little volume. By adjusting spring force and improving sensitivity, the probe can be used in CMM. Errors of the probe are analysed. Performances of the probe are verified by test of measuring force, verification of precision of single axis and plane precision.
基金the High Technology Research and Development Programme of china.
文摘Sonar image processing system is an important intelligent system of Autonomous Un-derwater Vehicle.Based on TMS320C30 high speed DSP,it is used to realize sonar imagecompression and underwater object detections including obstacle recognition in real time.Inthis paper,the software and hardware designs of this system are introduced and the experi-mental results are given.