According to the practical problems in eddy current sorting,the method and technology of eddy current hardness sorting based on LeastSquaresSupportVectorMachine(LS-SVM)are proposed based on the Xilinx Artix-7 FPGA in ...According to the practical problems in eddy current sorting,the method and technology of eddy current hardness sorting based on LeastSquaresSupportVectorMachine(LS-SVM)are proposed based on the Xilinx Artix-7 FPGA in this paper.The calculated sorting-hyperplane and designed sorting decision-making machine were used to sort different hardness of the vavles.The experimental results of the vavle sorting show that the sorting success rate can reach 100%under conditions that the number of test vavles is one quarter of the training vavles.The method and technology based on LS-SVM can solve the problems that the impedance feature value is nonlinear with the hardness value and variable sorting interval.It also proved that the LS-SVM algorithm has strong practical value in online eddy current sorting.展开更多
An ultra-thin flexible eddy current proximity sensor array was developed for online measurements of tiny gaps between large smooth metallic and nonmetallic surfaces of arbitrary shapes. The probe of the flexible eddy ...An ultra-thin flexible eddy current proximity sensor array was developed for online measurements of tiny gaps between large smooth metallic and nonmetallic surfaces of arbitrary shapes. The probe of the flexible eddy current sensor array, which includes a set of sensor coils, is fabricated on a thin flexible substrate using the flexible printed circuit board process which allows the probe to be very thin and flexible so that it can conform to the surface geometry of the measured objects. The sensor coils are connected to an inductance-capacitance oscillator, which converts the distance between the sensor coil and the metallic target to a frequency output. Experimental results show that the measurement accuracy of the sensor system can reach ±0.5% for a 2-mm gap and the sensor system is suitable for online gap measurements.展开更多
A 1.5-layer quasi-geostrophic reduced gravity ocean circulation model is used to study the propagation of mesoscale eddies across a western boundary current(WBC) either leaping across or penetrating in an anti-cycloni...A 1.5-layer quasi-geostrophic reduced gravity ocean circulation model is used to study the propagation of mesoscale eddies across a western boundary current(WBC) either leaping across or penetrating in an anti-cyclonic path through the gap. The steady leaping WBC nearly blocks all eddies from propagating across it through the gap completely. However, both cyclonic and anti-cyclonic eddies can migrate across a penetrating WBC in the vicinity of a gap, while inducing an opposite type of eddies on the cyclonic side of the WBC by weakening or strengthening the intrusion of the WBC. Both type of eddies gained strength from the WBC in the course of the propagation across the WBC in the gap. Eddies approaching the gap from the upstream are found to migrate more easily into the western basin due to the advection of the WBC. The migration speeds of the eddies are almost unchanged by the presence of the WBC in all experiments.展开更多
Large eddy simulation is performed to study three-dimensional wave-current interaction with a square cylinder at different Reynolds numbers, ranging from 1,000 to 600,000. The Keulegan-Carpenter number is relevantly a...Large eddy simulation is performed to study three-dimensional wave-current interaction with a square cylinder at different Reynolds numbers, ranging from 1,000 to 600,000. The Keulegan-Carpenter number is relevantly a constant of 0.6 for all cases. The Strouhal number, the mean and the RMS values of the effective drag coefficient in the streamwise and transverse directions are computed for various Reynolds numbers, and the velocity of a rep- resentative point in the turbulent zone is simulated to find the turbulent feature. It is found that the wave-current interaction should be considered as three-dimensional flow when the Reynolds number is high; under wave-current effect, there exists a critical Reynolds number, and when the Reynolds number is smaller than the critical one, current effect on wave can be nearly neglected; conversely, with the Reynolds number increasing, wave-currentstructure interaction is sensitive to the Reynolds number.展开更多
基金supported by a project of the National Natural Science Foundation(No.51865004)the Guizhou Science and Technology Department(No.QKH20161081,No.QKH20192881)
文摘According to the practical problems in eddy current sorting,the method and technology of eddy current hardness sorting based on LeastSquaresSupportVectorMachine(LS-SVM)are proposed based on the Xilinx Artix-7 FPGA in this paper.The calculated sorting-hyperplane and designed sorting decision-making machine were used to sort different hardness of the vavles.The experimental results of the vavle sorting show that the sorting success rate can reach 100%under conditions that the number of test vavles is one quarter of the training vavles.The method and technology based on LS-SVM can solve the problems that the impedance feature value is nonlinear with the hardness value and variable sorting interval.It also proved that the LS-SVM algorithm has strong practical value in online eddy current sorting.
文摘An ultra-thin flexible eddy current proximity sensor array was developed for online measurements of tiny gaps between large smooth metallic and nonmetallic surfaces of arbitrary shapes. The probe of the flexible eddy current sensor array, which includes a set of sensor coils, is fabricated on a thin flexible substrate using the flexible printed circuit board process which allows the probe to be very thin and flexible so that it can conform to the surface geometry of the measured objects. The sensor coils are connected to an inductance-capacitance oscillator, which converts the distance between the sensor coil and the metallic target to a frequency output. Experimental results show that the measurement accuracy of the sensor system can reach ±0.5% for a 2-mm gap and the sensor system is suitable for online gap measurements.
基金Supported by the National Program on Global Change and Air-Sea Interaction(Nos.GASI-03-01-01-05,GASI-IPOVAI-01-02,GASIIPOVAI-02,GASI-IPOVAI-03,GASI-IPOVAI-01-05,GASI-03-01-01-02)the National Natural Science Foundation of China(Nos.41421005,41720104008,41476025,41376038,41206019)+4 种基金the Shandong Joint Fund for Marine Science Research Centers(Nos.U1606402,U1606405)the CAS Strategic Priority Project(No.XDA11010205)the Scientific and Technological Innovation Project of Qingdao National Laboratory for Marine Science and Technology(No.2016ASKJ04)the National Science and Technology Major Project(No.2016ZX05057015)the Open Fund of Shandong Provincial Key Laboratory of Marine Ecology and Environment&Disaster Prevention and Mitigation(No.201701)
文摘A 1.5-layer quasi-geostrophic reduced gravity ocean circulation model is used to study the propagation of mesoscale eddies across a western boundary current(WBC) either leaping across or penetrating in an anti-cyclonic path through the gap. The steady leaping WBC nearly blocks all eddies from propagating across it through the gap completely. However, both cyclonic and anti-cyclonic eddies can migrate across a penetrating WBC in the vicinity of a gap, while inducing an opposite type of eddies on the cyclonic side of the WBC by weakening or strengthening the intrusion of the WBC. Both type of eddies gained strength from the WBC in the course of the propagation across the WBC in the gap. Eddies approaching the gap from the upstream are found to migrate more easily into the western basin due to the advection of the WBC. The migration speeds of the eddies are almost unchanged by the presence of the WBC in all experiments.
基金supported by the National Natural Science Foundation of China (No. 51178397)Technological Research and Development Programs of the Ministry of Railways (No. 2010G004-L)
文摘Large eddy simulation is performed to study three-dimensional wave-current interaction with a square cylinder at different Reynolds numbers, ranging from 1,000 to 600,000. The Keulegan-Carpenter number is relevantly a constant of 0.6 for all cases. The Strouhal number, the mean and the RMS values of the effective drag coefficient in the streamwise and transverse directions are computed for various Reynolds numbers, and the velocity of a rep- resentative point in the turbulent zone is simulated to find the turbulent feature. It is found that the wave-current interaction should be considered as three-dimensional flow when the Reynolds number is high; under wave-current effect, there exists a critical Reynolds number, and when the Reynolds number is smaller than the critical one, current effect on wave can be nearly neglected; conversely, with the Reynolds number increasing, wave-currentstructure interaction is sensitive to the Reynolds number.
