Developed independently by China,HJ-1A/B satellites have operated well on-orbit for five years and acquired a large number of high-quality observation data.The realization of the observation data geometric precision c...Developed independently by China,HJ-1A/B satellites have operated well on-orbit for five years and acquired a large number of high-quality observation data.The realization of the observation data geometric precision correction is of great significance for macro and dynamic ecological environment monitoring.The paper analyzed the parameter characteristics of HJ-1 satellite and geometric features of HJ-1 satellite level 2 data(systematic geo- corrected data).Based on this,the overall HJ- 1 multi- sensor geometric correction flow and charge-coupled device(CCD) automatic geometric precision correction method were designed.Actual operating data showed that the method could achieve good result for automatic geometric precision correction of HJ-1 satellite data,automatic HJ-1 CCD image geometric precision correction accuracy could be achieved within two pixels and automatic matching accuracy between the images of same satellite could be obtained less than one pixel.展开更多
In recent years, aluminum alloy profiles have been applied more and more widely in the industrial field, and more frequently in automobile, aerospace, electronics and other industries. At present, in the aluminum prof...In recent years, aluminum alloy profiles have been applied more and more widely in the industrial field, and more frequently in automobile, aerospace, electronics and other industries. At present, in the aluminum profile manufacturing enterprises in our country, there are some problems in the processing of industrial aluminum profiles, such as insufficient research and development capacity and imperfect equipment, which seriously restrict the development of the processing and production of industrial aluminum profiles in our country. This paper discusses the characteristics, application, production process and key points in the production process of industrial aluminum alloy profiles, and realizes the process requirements of subsequent mechanical processing by optimizing the process and designing and manufacturing tooling tools!展开更多
Soft computing tools in the form of combination of multiple nonlinear regression and M5′ model tree were used for estimation of overtopping rate at the vertical coastal structures. For reliable and precise estimation...Soft computing tools in the form of combination of multiple nonlinear regression and M5′ model tree were used for estimation of overtopping rate at the vertical coastal structures. For reliable and precise estimation of overtopping rate, the experimental data available in the database CLASH were used. The dimensionless overtopping rate was estimated in terms of conventional dimensionless parameters including the relative crest freeboard Rc/Hs, seabed slope tanθ, deep water wave steepness S(om), surf similarity ξ(om) and local relative water depth ht/Hs. The accuracy of the new model was compared with other existing models and also evaluated with some field measurements. The results indicated that the model presented in this paper is more accurate than other existing models. With statistical parameters, it is shown that the accuracy of predictions in the new model is better than that of other models.展开更多
文摘Developed independently by China,HJ-1A/B satellites have operated well on-orbit for five years and acquired a large number of high-quality observation data.The realization of the observation data geometric precision correction is of great significance for macro and dynamic ecological environment monitoring.The paper analyzed the parameter characteristics of HJ-1 satellite and geometric features of HJ-1 satellite level 2 data(systematic geo- corrected data).Based on this,the overall HJ- 1 multi- sensor geometric correction flow and charge-coupled device(CCD) automatic geometric precision correction method were designed.Actual operating data showed that the method could achieve good result for automatic geometric precision correction of HJ-1 satellite data,automatic HJ-1 CCD image geometric precision correction accuracy could be achieved within two pixels and automatic matching accuracy between the images of same satellite could be obtained less than one pixel.
文摘In recent years, aluminum alloy profiles have been applied more and more widely in the industrial field, and more frequently in automobile, aerospace, electronics and other industries. At present, in the aluminum profile manufacturing enterprises in our country, there are some problems in the processing of industrial aluminum profiles, such as insufficient research and development capacity and imperfect equipment, which seriously restrict the development of the processing and production of industrial aluminum profiles in our country. This paper discusses the characteristics, application, production process and key points in the production process of industrial aluminum alloy profiles, and realizes the process requirements of subsequent mechanical processing by optimizing the process and designing and manufacturing tooling tools!
文摘Soft computing tools in the form of combination of multiple nonlinear regression and M5′ model tree were used for estimation of overtopping rate at the vertical coastal structures. For reliable and precise estimation of overtopping rate, the experimental data available in the database CLASH were used. The dimensionless overtopping rate was estimated in terms of conventional dimensionless parameters including the relative crest freeboard Rc/Hs, seabed slope tanθ, deep water wave steepness S(om), surf similarity ξ(om) and local relative water depth ht/Hs. The accuracy of the new model was compared with other existing models and also evaluated with some field measurements. The results indicated that the model presented in this paper is more accurate than other existing models. With statistical parameters, it is shown that the accuracy of predictions in the new model is better than that of other models.