The global distributions of eight principal tidal constituents, M2, S2, K1, O1, N2, K2, P1, and Q1, are derived using TOPEX/Poseidon and JASON-1（T/P-J） satellite altimeter data for 16 a. The intercomparison of the d...The global distributions of eight principal tidal constituents, M2, S2, K1, O1, N2, K2, P1, and Q1, are derived using TOPEX/Poseidon and JASON-1（T/P-J） satellite altimeter data for 16 a. The intercomparison of the derived harmonics at 7000 subsatellite track crossover points shows that the root mean square （RMS） values of the tidal height differences of the above eight constituents range from 1.19 cm to 2.67 cm, with an average of about 2 cm. The RMS values of the tidal height differences between T/P-J solutions and the harmonics from ground measurements at 152 tidal gauge stations for the above constituents range from 0.34 cm to 1.08 cm, and the relative deviations range from 0.031 to 0.211. The root sum square of the RMS differences of these eight constituents is 2.12 cm, showing the improvement of the present model over the existing global ocean tidal models. Based on the obtained tidal model the global ocean tidal energetics is studied and the global distribution of the tidal power input density by tide-generating force of each constituent is calculated, showing that the power input source regions of semidiurnal tides are mainly concentrated in the tropical belt between 30S and 30N, while the power input source regions of diurnal tides are mainly concentrated off the tropic oceans. The global energy dissipation rates of the M2, S2, K1, O1, N2, P1, K2 and Q1 tides are 2.424, 0.401, 0.334, 0.160, 0.113, 0.035, 0.030 and 0.006 TW, respectively. The total global tidal dissipation rate of these eight constituents amounts to 3.5 TW.展开更多
Study results of low temperature effects on the strength index and specific power input into rock failure are presented.It has been experimentally determined that within the range of-5 °С to-15 °С,there is...Study results of low temperature effects on the strength index and specific power input into rock failure are presented.It has been experimentally determined that within the range of-5 °С to-15 °С,there is a local minimum at which the compression strength and specific power input into failure of some rocks are 10%-50% lower than those at positive temperatures.展开更多
The study focuses on estimating the input power of a power plant from available data, using the theoretical inverter efficiency as the key parameter. The paper addresses the problem of missing data in power generation...The study focuses on estimating the input power of a power plant from available data, using the theoretical inverter efficiency as the key parameter. The paper addresses the problem of missing data in power generation systems and proposes an approach based on the efficiency formula widely documented in the literature. In the absence of input data, this method makes it possible to estimate the plant’s input power using data extracted from the site, in particular that provided by the Ministry of the Environment. The importance of this study lies in the need to accurately determine the input power in order to assess the overall performance of the energy system.展开更多
It is very important to predict the coupling between the cavity and the high power input source in the coupler design. In this paper, a time domain method is used to calculate the external quality factor Qext for the ...It is very important to predict the coupling between the cavity and the high power input source in the coupler design. In this paper, a time domain method is used to calculate the external quality factor Qext for the BEPC Ⅱ superconducting cavity. A comparison between simulation results and experimental results is presented. The results of simulation and measurement of Qext have a good agreement within an error of 10%. The geometry parameters related with Qext are also studied.展开更多
The BEPCII storage ring adopts two 500 MHz superconducting cavities （SCC）. Each one is equipped with a 500 MHz input power coupler. The coupler is to feed 150 kW power in continuous wave （CW） mode with both standi...The BEPCII storage ring adopts two 500 MHz superconducting cavities （SCC）. Each one is equipped with a 500 MHz input power coupler. The coupler is to feed 150 kW power in continuous wave （CW） mode with both standing and traveling wave modes. Due to high power feeding and high frequency of the coupler, its fabrication is a big challenge. The fabrication started with two key components, the window and the antenna. Up to now, two sets including windows and antennas have been made by IHEP. And a 270 kW RF power in CW has passed through the coupler during the high power test. The fabrication details are presented in this paper.展开更多
A method for the optimal fiber input power determination is presented by employing the variation characteristics of signal to noise ratio(SNR) in spontaneous Brillouin-scattering-based sensing system. And a heterodyne...A method for the optimal fiber input power determination is presented by employing the variation characteristics of signal to noise ratio(SNR) in spontaneous Brillouin-scattering-based sensing system. And a heterodyne detection system is constructed for measuring the Brillouin scattering spectra with different fiber input powers. The Brillouin spectrum width and system SNR can be simultaneously measured from these spectra, and the optimal fiber input power can be obtained from such information. In the experiment, for 48.8-km-long standard single-mode fiber(SSMF), the optimal fiber input power values are all approximately 0 dBm obtained by the maximum SNR position for different local oscillator power values and average times.展开更多
Input power is an important indicator for the safety testing of electrical and electronic products.Smart toilets have been frequently detected that the actual input power is inconsistent with the nominal power.Researc...Input power is an important indicator for the safety testing of electrical and electronic products.Smart toilets have been frequently detected that the actual input power is inconsistent with the nominal power.Research and analysis show that the accuracy of the input power measurement results of the smart toilet mainly depends on the temperature control principle and power test method of the product.This article mainly discusses the characteristics of product temperature control,the testing method of mean and peak power and its characteristics,which will provide reference for the input power test of the smart toilet,and will improve the accuracy of power measurement.展开更多
In high voltage input DC-DC converter, auxiliary winding of isolation transformer is usually used to supply power for control circuit. Due to the wide-range of input voltage, the variable output voltage of auxiliary w...In high voltage input DC-DC converter, auxiliary winding of isolation transformer is usually used to supply power for control circuit. Due to the wide-range of input voltage, the variable output voltage of auxiliary winding will cause a series of problems, such as variable drive pulse amplitude, increased driver switching devices loss and drive transformer core saturation. This paper analyzes the influence of variable output voltage of auxiliary winding in detail. A novel method is proposed to solve the problem of large variation range of auxiliary winding output voltage, which is adding a buck converter between the auxiliary winding and the control circuit. A dual switch forward convert has been designed with 300 V - 800 V input and 24 V/5 A output. The results show that this method is effective by comparing the different results of using buck converter or not.展开更多
基金The National Natural Science Foundation of China under contract No. 40676009 and 40606006the Basic Research Project of Qingdao Science and Technology Program under contract No. 11-1-4-98-jch
文摘The global distributions of eight principal tidal constituents, M2, S2, K1, O1, N2, K2, P1, and Q1, are derived using TOPEX/Poseidon and JASON-1（T/P-J） satellite altimeter data for 16 a. The intercomparison of the derived harmonics at 7000 subsatellite track crossover points shows that the root mean square （RMS） values of the tidal height differences of the above eight constituents range from 1.19 cm to 2.67 cm, with an average of about 2 cm. The RMS values of the tidal height differences between T/P-J solutions and the harmonics from ground measurements at 152 tidal gauge stations for the above constituents range from 0.34 cm to 1.08 cm, and the relative deviations range from 0.031 to 0.211. The root sum square of the RMS differences of these eight constituents is 2.12 cm, showing the improvement of the present model over the existing global ocean tidal models. Based on the obtained tidal model the global ocean tidal energetics is studied and the global distribution of the tidal power input density by tide-generating force of each constituent is calculated, showing that the power input source regions of semidiurnal tides are mainly concentrated in the tropical belt between 30S and 30N, while the power input source regions of diurnal tides are mainly concentrated off the tropic oceans. The global energy dissipation rates of the M2, S2, K1, O1, N2, P1, K2 and Q1 tides are 2.424, 0.401, 0.334, 0.160, 0.113, 0.035, 0.030 and 0.006 TW, respectively. The total global tidal dissipation rate of these eight constituents amounts to 3.5 TW.
文摘Study results of low temperature effects on the strength index and specific power input into rock failure are presented.It has been experimentally determined that within the range of-5 °С to-15 °С,there is a local minimum at which the compression strength and specific power input into failure of some rocks are 10%-50% lower than those at positive temperatures.
文摘The study focuses on estimating the input power of a power plant from available data, using the theoretical inverter efficiency as the key parameter. The paper addresses the problem of missing data in power generation systems and proposes an approach based on the efficiency formula widely documented in the literature. In the absence of input data, this method makes it possible to estimate the plant’s input power using data extracted from the site, in particular that provided by the Ministry of the Environment. The importance of this study lies in the need to accurately determine the input power in order to assess the overall performance of the energy system.
基金Supported by National Natural Science Foundation of China(k711360503)
文摘It is very important to predict the coupling between the cavity and the high power input source in the coupler design. In this paper, a time domain method is used to calculate the external quality factor Qext for the BEPC Ⅱ superconducting cavity. A comparison between simulation results and experimental results is presented. The results of simulation and measurement of Qext have a good agreement within an error of 10%. The geometry parameters related with Qext are also studied.
基金Supported by National Natural Science Foundation of China (k711360503)
文摘The BEPCII storage ring adopts two 500 MHz superconducting cavities （SCC）. Each one is equipped with a 500 MHz input power coupler. The coupler is to feed 150 kW power in continuous wave （CW） mode with both standing and traveling wave modes. Due to high power feeding and high frequency of the coupler, its fabrication is a big challenge. The fabrication started with two key components, the window and the antenna. Up to now, two sets including windows and antennas have been made by IHEP. And a 270 kW RF power in CW has passed through the coupler during the high power test. The fabrication details are presented in this paper.
基金supported by the National Natural Science Foundation of China(No.61377088)the Natural Science Foundation of Hebei Province of China(Nos.E2015502053 and F2014502098)
文摘A method for the optimal fiber input power determination is presented by employing the variation characteristics of signal to noise ratio(SNR) in spontaneous Brillouin-scattering-based sensing system. And a heterodyne detection system is constructed for measuring the Brillouin scattering spectra with different fiber input powers. The Brillouin spectrum width and system SNR can be simultaneously measured from these spectra, and the optimal fiber input power can be obtained from such information. In the experiment, for 48.8-km-long standard single-mode fiber(SSMF), the optimal fiber input power values are all approximately 0 dBm obtained by the maximum SNR position for different local oscillator power values and average times.
文摘Input power is an important indicator for the safety testing of electrical and electronic products.Smart toilets have been frequently detected that the actual input power is inconsistent with the nominal power.Research and analysis show that the accuracy of the input power measurement results of the smart toilet mainly depends on the temperature control principle and power test method of the product.This article mainly discusses the characteristics of product temperature control,the testing method of mean and peak power and its characteristics,which will provide reference for the input power test of the smart toilet,and will improve the accuracy of power measurement.
文摘In high voltage input DC-DC converter, auxiliary winding of isolation transformer is usually used to supply power for control circuit. Due to the wide-range of input voltage, the variable output voltage of auxiliary winding will cause a series of problems, such as variable drive pulse amplitude, increased driver switching devices loss and drive transformer core saturation. This paper analyzes the influence of variable output voltage of auxiliary winding in detail. A novel method is proposed to solve the problem of large variation range of auxiliary winding output voltage, which is adding a buck converter between the auxiliary winding and the control circuit. A dual switch forward convert has been designed with 300 V - 800 V input and 24 V/5 A output. The results show that this method is effective by comparing the different results of using buck converter or not.
