In accordance with the timely weather report and routine meteorological resources of the meteorological observatory of Liaoning Province from 1979 to 2009,durative fog occurred in Liaoning and their characteristics we...In accordance with the timely weather report and routine meteorological resources of the meteorological observatory of Liaoning Province from 1979 to 2009,durative fog occurred in Liaoning and their characteristics were counted and analyzed in this paper.The report showed that the continuous hazy days occurred three times in 30 years and they had large chances to take place in winter.After the heavy precipitation in the North China and Northeast China,temperature in every place turned up again.If under such circumstances,expansion and temperature inversion happened in the 925 hPa and the wind speed was slower than 4 to 8 m/s in the 1 000 hPa,continuous hazy days happened.展开更多
Previous literature shows that scholars differ considerably on what zai and-zhe indicate.By making use of an oral speech corpus,we analyzed and tested the data with regard to the functions of "zai" and "...Previous literature shows that scholars differ considerably on what zai and-zhe indicate.By making use of an oral speech corpus,we analyzed and tested the data with regard to the functions of "zai" and "-zhe" and found that zai indicates the action is in progress,and it is narrative,while-zhe expresses the ongoing state of an action and is descriptive;-zhe can be used after the first verb in a serial verbal con struction to indicate the accompanying action,while zai does not have this function;in complex sentences,the zai clause is temporal in na ture while-zhe clause is treated as a manner adverbial.展开更多
With an effective bianisotropy picture, high-frequency behaviours of different magnetic materials can be reconciled, and the higher permeability and higher resonance frequencies are achieved even in the GHz range. The...With an effective bianisotropy picture, high-frequency behaviours of different magnetic materials can be reconciled, and the higher permeability and higher resonance frequencies are achieved even in the GHz range. The validity of the bianisotropy picture is quantitatively verified by the in-plane anisotropic Fe34Co55Zr11 thin films. A prolate elliptical precession of the magnetization about its equilibrium direction is the key point, which can be induced by an artificial or an intrinsic bianisotropy system.展开更多
Employing the compatibility method, we obtain the symmetries of the （3＋1）-dimensional Kadomtsev Petviashvili （KP） equation. Four types of similarity reductions of the KP equation are obtained by solving the corre...Employing the compatibility method, we obtain the symmetries of the （3＋1）-dimensional Kadomtsev Petviashvili （KP） equation. Four types of similarity reductions of the KP equation are obtained by solving the corresponding characteristic equations associated with symmetry equations. In addition, a lot of similarity solutions to the KP equation are obtadned.展开更多
Based on 740 stations of daily precipitation datasets in China, the precipitationconcentration degree （PCD） and precipitation-concentration period （PCP） of different intensity durative precipitation events were ca...Based on 740 stations of daily precipitation datasets in China, the precipitationconcentration degree （PCD） and precipitation-concentration period （PCP） of different intensity durative precipitation events were calculated to analyze their statistical characteristics, mainly including spatial and temporal distributions, variations and climatic trends of the two parameters of the durative heavy precipitation events in China. It is proved that these two parameters of heavy rainfall can display the temporal inhomogeneity in the precipitation field. And it is also found that there is a good positive relationship between the precipitation-concentration degree and annual rainfall amount in the Eastern and Central China. This method can be anolied in flood assessment and climate change fields.展开更多
The conformal meehanico-electrical systems are presented by infinitesimal point transformations of time and generalized coordinates. The necessary and suflleient conditions that the eonformal meehanieo-eleetrieal syst...The conformal meehanico-electrical systems are presented by infinitesimal point transformations of time and generalized coordinates. The necessary and suflleient conditions that the eonformal meehanieo-eleetrieal systems possess Lie symmetry are given. The Noether conserved quantities of the eonformal meehanieo-eleetrieal systems are obtained from Lie symmetries.展开更多
The optical emission spectroscopy of a surface dielectric barrier discharge plasma aerodynamic actuator is investigated with different electrode configurations, applied voltages and driving frequencies. The rotational...The optical emission spectroscopy of a surface dielectric barrier discharge plasma aerodynamic actuator is investigated with different electrode configurations, applied voltages and driving frequencies. The rotational temperature of N2 （C^3 Ⅱu） molecule is calculated according to its rotational emission band near 380.5 nm. The average electron energy of the discharge is evaluated by emission intensity ratio of first negative system to second positive system of N2. The rotational temperature is sensitive to the inner space of an electrode pair. The average electron energy shows insensitivity to the applied voltage, the driving frequency and the electrode configuration.展开更多
A modified BISQ （Blot/Squirt） model for wave propagation in low-permeability sandstone is developed by introducing the viscoelastic mechanism of a porous skeleton into Dvorkin＇s model. The linear viscoelasticity of...A modified BISQ （Blot/Squirt） model for wave propagation in low-permeability sandstone is developed by introducing the viscoelastic mechanism of a porous skeleton into Dvorkin＇s model. The linear viscoelasticity of the Kelvin Voigt constitutive law is employed to describe the stress-strain relation of a solid frame with clay while the ultrasonic waves propagate through the fluid-saturated sandstone. The phase velocity and attenuation of two p-waves are given based on the present BISQ model. The comparisons between numerical results and experimental data indicate that our viscoelastic model is more realistic and feasible for wave propagation in the low-permeability sandstone, especially with clay, than traditional BISQ models.展开更多
The dye injection and hydrogen bubble visualization techniques are used to investigate the dual-vortex structure including its development, breakdown and the spatial location of vortex core over nonslender delta wings...The dye injection and hydrogen bubble visualization techniques are used to investigate the dual-vortex structure including its development, breakdown and the spatial location of vortex core over nonslender delta wings. It is concluded that the dual-vortex structure can be affected significantly by sweep angle and Reynolds number, and generated only at small angle of attack. The angle between the projection of outer vortex core on delta wing surface and the root chord line has nothing to do with the Reynolds Number and angle of attack, but has simple linear relation with the sweep angle of the model tested.展开更多
Factors influencing the quality of lensless ghost imaging are investigated. According to the experimental results, we find that the imaging quality is determined by the number of independent sub light sources on the i...Factors influencing the quality of lensless ghost imaging are investigated. According to the experimental results, we find that the imaging quality is determined by the number of independent sub light sources on the imaging plane of the reference arm. A qualitative picture based on advanced wave optics is presented to explain the physics behind the experimental phenomena. The present results will be helpful to provide a basis for improving the quality of ghost imaging systems in future works.展开更多
The layer structure of InGaAs/InP double heterojunction bipolar transistor （DHBT） is designed to enhance the frequency performance and breakdown voltage. The composition-graded base structure is used to decrease the...The layer structure of InGaAs/InP double heterojunction bipolar transistor （DHBT） is designed to enhance the frequency performance and breakdown voltage. The composition-graded base structure is used to decrease the base transit time. The InGaAs setback layer and two highly doped InGaAsP layers are used to eliminate the conduction band spike of the collector. The submicron-emitter InGaAs/InP DHBT is fabricated successfully. The base contact resistance is greatly decreased by optimization of contact metals. The breakdown voltage is more than 6 V. The current gain cutoff frequency is as high as 170 GHz and the maximum oscillation frequency reached 253 GHz. The DHBT with such high performances can be used to make W-band power amplifier.展开更多
Our understanding of the rapid neutron capture nucleosynthesis process in universe depends on the reliability of nuclear mass predictions. Initiated by the newly developed mass table in the relativistic mean field the...Our understanding of the rapid neutron capture nucleosynthesis process in universe depends on the reliability of nuclear mass predictions. Initiated by the newly developed mass table in the relativistic mean field theory （RMF）, we investigate the influence of mass models on the r-process calculations, assuming the same astrophysical conditions. The different model predictions on the so far unreachable nuclei lead to significant deviations in the calculated ^-process abundances.展开更多
A simple spherical bead and pulsating spherical sound source model are proposed to investigate the effect of multiple scattering between the head and the sound source on near-field head-related transfer function （HRT...A simple spherical bead and pulsating spherical sound source model are proposed to investigate the effect of multiple scattering between the head and the sound source on near-field head-related transfer function （HRTF） measurement. Multipole expansion method is used to calculate HRTFs of the model, then the relationships among the magnitude error of HRTF with frequency, source direction, source size, and the distance between the head centre and the sound source are analysed. The results show that to ensure the magnitude error of HRTF within 1.0dB up to 20kHz, for source distance not less than 0.15m or 0.20m, the radius of the sound source should not exceed 0.03 m or 0.05 m, respectively. The conclusion suggests an appropriate size of sound source in near-field HRTF measurement.展开更多
We propose a modified form of Wigner functions for generic non-Hamiltonian systems on noncommutative space and prove that it satisfies the corresponding ＊-genvalue equation. In addition, as an example, we derive exac...We propose a modified form of Wigner functions for generic non-Hamiltonian systems on noncommutative space and prove that it satisfies the corresponding ＊-genvalue equation. In addition, as an example, we derive exact energy spectra and Wigner functions for a non-Hamiltonian toy model on the noncommutative space.展开更多
Phase comparison method can enhance the measurement resolution to 10^-13/T in time domain. This method can also be used in distance measurement in the navigation and positioning. We propose a super high-resolution dis...Phase comparison method can enhance the measurement resolution to 10^-13/T in time domain. This method can also be used in distance measurement in the navigation and positioning. We propose a super high-resolution distance measurement based on linear phase comparison method. A high resolution scheme is put forward on the basis of the research of major factors concerning the phase comparison in the distance measurement. Conversion of a high-linearity phase difference to voltage and high-resolution voltage meter make it possible to obtain a very high phase measurement resolution. When the purpose is to measure distance, the phase noise of frequency source used in the measurement can be reduced partly. Thus this method is favourable for high resolution distance measurement. The precision of the distance measurement can reach 0.1c ps with c being the velocity of light in vacuum.展开更多
A four-finger InGaAs/InP double hetero3unction bipolar transistor is designed and fabricated successfully by using planacization technology. The emitter area of each finger is 1 × 15 um^2. The breakdown voltage i...A four-finger InGaAs/InP double hetero3unction bipolar transistor is designed and fabricated successfully by using planacization technology. The emitter area of each finger is 1 × 15 um^2. The breakdown voltage is more than 7V, the maximum collector current could be more than lOOmA. The current gain cutoff frequency is as high as 155 GHz and the maximum oscillation frequency reaches 253 GHz. The heterostructure bipolar transistor can offer more than 70row class-A maximum output power at W band and the maximum power density can be as high as 1.2 W/mm.展开更多
One iterative in Grover＇s original quantum search algorithm consists of two Hadamard-Walsh transformations, a selective amplitude inversion and a diffusion amplitude inversion. We concentrate on the relation among th...One iterative in Grover＇s original quantum search algorithm consists of two Hadamard-Walsh transformations, a selective amplitude inversion and a diffusion amplitude inversion. We concentrate on the relation among the probability of success of the algorithm, the phase shifts, the number of target items and the number of iterations via replacing the two amplitude inversions by phase shifts of an arbitrary φ = ψ（0 ≤, ψ≤ 27r）. Then, according to the relation we find out the optimal phase shifts when the number of iterations is given. We present a new quantum search algorithm based on the optimal phase shifts of 1.018 after 0.57π√M/N iterations. The new algorithm can obtain either a single target item or multiple target items in the search space with the probability of success at least 93.43%展开更多
文摘In accordance with the timely weather report and routine meteorological resources of the meteorological observatory of Liaoning Province from 1979 to 2009,durative fog occurred in Liaoning and their characteristics were counted and analyzed in this paper.The report showed that the continuous hazy days occurred three times in 30 years and they had large chances to take place in winter.After the heavy precipitation in the North China and Northeast China,temperature in every place turned up again.If under such circumstances,expansion and temperature inversion happened in the 925 hPa and the wind speed was slower than 4 to 8 m/s in the 1 000 hPa,continuous hazy days happened.
文摘Previous literature shows that scholars differ considerably on what zai and-zhe indicate.By making use of an oral speech corpus,we analyzed and tested the data with regard to the functions of "zai" and "-zhe" and found that zai indicates the action is in progress,and it is narrative,while-zhe expresses the ongoing state of an action and is descriptive;-zhe can be used after the first verb in a serial verbal con struction to indicate the accompanying action,while zai does not have this function;in complex sentences,the zai clause is temporal in na ture while-zhe clause is treated as a manner adverbial.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10774062, 10774061 and 90505007. The authors thank Y. D. Zhang and D. P. Yang for fruitful discussions.
文摘With an effective bianisotropy picture, high-frequency behaviours of different magnetic materials can be reconciled, and the higher permeability and higher resonance frequencies are achieved even in the GHz range. The validity of the bianisotropy picture is quantitatively verified by the in-plane anisotropic Fe34Co55Zr11 thin films. A prolate elliptical precession of the magnetization about its equilibrium direction is the key point, which can be induced by an artificial or an intrinsic bianisotropy system.
基金Supported by the Natural Science Foundation of Shandong Province under Grant No Q2005A01.
文摘Employing the compatibility method, we obtain the symmetries of the （3＋1）-dimensional Kadomtsev Petviashvili （KP） equation. Four types of similarity reductions of the KP equation are obtained by solving the corresponding characteristic equations associated with symmetry equations. In addition, a lot of similarity solutions to the KP equation are obtadned.
基金Concentrated fund item of nationalscience and technology foundation work,No.2001DEA30029-0604Jiangsunaturalsciencefoundation,No.BK2005163
文摘Based on 740 stations of daily precipitation datasets in China, the precipitationconcentration degree （PCD） and precipitation-concentration period （PCP） of different intensity durative precipitation events were calculated to analyze their statistical characteristics, mainly including spatial and temporal distributions, variations and climatic trends of the two parameters of the durative heavy precipitation events in China. It is proved that these two parameters of heavy rainfall can display the temporal inhomogeneity in the precipitation field. And it is also found that there is a good positive relationship between the precipitation-concentration degree and annual rainfall amount in the Eastern and Central China. This method can be anolied in flood assessment and climate change fields.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10672143 and 60575055, and the Natural Science Foundation of Henan Province under Grant No 0511022200.
文摘The conformal meehanico-electrical systems are presented by infinitesimal point transformations of time and generalized coordinates. The necessary and suflleient conditions that the eonformal meehanieo-eleetrieal systems possess Lie symmetry are given. The Noether conserved quantities of the eonformal meehanieo-eleetrieal systems are obtained from Lie symmetries.
文摘The optical emission spectroscopy of a surface dielectric barrier discharge plasma aerodynamic actuator is investigated with different electrode configurations, applied voltages and driving frequencies. The rotational temperature of N2 （C^3 Ⅱu） molecule is calculated according to its rotational emission band near 380.5 nm. The average electron energy of the discharge is evaluated by emission intensity ratio of first negative system to second positive system of N2. The rotational temperature is sensitive to the inner space of an electrode pair. The average electron energy shows insensitivity to the applied voltage, the driving frequency and the electrode configuration.
基金Supported by the National Natural Science Foundation of China for Distinguished Young Scholars under Grant No 40725012, the National High-Tech Research and Development Programme of China under Grant No 2006AA06Z240, the National Key Basic Research Programme of China under Grant No 2007CB209505, and the CNPC International Science and Technology Cooperation Project （2006DFB62030）.
文摘A modified BISQ （Blot/Squirt） model for wave propagation in low-permeability sandstone is developed by introducing the viscoelastic mechanism of a porous skeleton into Dvorkin＇s model. The linear viscoelasticity of the Kelvin Voigt constitutive law is employed to describe the stress-strain relation of a solid frame with clay while the ultrasonic waves propagate through the fluid-saturated sandstone. The phase velocity and attenuation of two p-waves are given based on the present BISQ model. The comparisons between numerical results and experimental data indicate that our viscoelastic model is more realistic and feasible for wave propagation in the low-permeability sandstone, especially with clay, than traditional BISQ models.
基金Supported by the National Natural Science Foundation of China under Grant No 10425207.
文摘The dye injection and hydrogen bubble visualization techniques are used to investigate the dual-vortex structure including its development, breakdown and the spatial location of vortex core over nonslender delta wings. It is concluded that the dual-vortex structure can be affected significantly by sweep angle and Reynolds number, and generated only at small angle of attack. The angle between the projection of outer vortex core on delta wing surface and the root chord line has nothing to do with the Reynolds Number and angle of attack, but has simple linear relation with the sweep angle of the model tested.
基金Supported by the National Natural Science Foundation of China under Grant No 60477007, the Hi-Tech Research and Development Programme of China under Grant No 2006AA12Z115, and Shanghai Fundamental Research Project under Grant No 06JC14069. The authors are sincerely grateful to the anonymous referees for their helpful comments.
文摘Factors influencing the quality of lensless ghost imaging are investigated. According to the experimental results, we find that the imaging quality is determined by the number of independent sub light sources on the imaging plane of the reference arm. A qualitative picture based on advanced wave optics is presented to explain the physics behind the experimental phenomena. The present results will be helpful to provide a basis for improving the quality of ghost imaging systems in future works.
文摘The layer structure of InGaAs/InP double heterojunction bipolar transistor （DHBT） is designed to enhance the frequency performance and breakdown voltage. The composition-graded base structure is used to decrease the base transit time. The InGaAs setback layer and two highly doped InGaAsP layers are used to eliminate the conduction band spike of the collector. The submicron-emitter InGaAs/InP DHBT is fabricated successfully. The base contact resistance is greatly decreased by optimization of contact metals. The breakdown voltage is more than 6 V. The current gain cutoff frequency is as high as 170 GHz and the maximum oscillation frequency reached 253 GHz. The DHBT with such high performances can be used to make W-band power amplifier.
基金Supported by the National Key Basic Research Programme of China under Grant No 2007CB815000, the National Natural Science Foundation of China under Grant Nos 104350107 10775004 and 10221003.
文摘Our understanding of the rapid neutron capture nucleosynthesis process in universe depends on the reliability of nuclear mass predictions. Initiated by the newly developed mass table in the relativistic mean field theory （RMF）, we investigate the influence of mass models on the r-process calculations, assuming the same astrophysical conditions. The different model predictions on the so far unreachable nuclei lead to significant deviations in the calculated ^-process abundances.
基金Supported by the National Natural Science Foundation of China under Grant No 10774049.
文摘A simple spherical bead and pulsating spherical sound source model are proposed to investigate the effect of multiple scattering between the head and the sound source on near-field head-related transfer function （HRTF） measurement. Multipole expansion method is used to calculate HRTFs of the model, then the relationships among the magnitude error of HRTF with frequency, source direction, source size, and the distance between the head centre and the sound source are analysed. The results show that to ensure the magnitude error of HRTF within 1.0dB up to 20kHz, for source distance not less than 0.15m or 0.20m, the radius of the sound source should not exceed 0.03 m or 0.05 m, respectively. The conclusion suggests an appropriate size of sound source in near-field HRTF measurement.
基金Supported by the National Natural Science Foundation of China under Grant 10675106 and the Talented Person Troop Items of Basic Construction of Anhui University.
文摘We propose a modified form of Wigner functions for generic non-Hamiltonian systems on noncommutative space and prove that it satisfies the corresponding ＊-genvalue equation. In addition, as an example, we derive exact energy spectra and Wigner functions for a non-Hamiltonian toy model on the noncommutative space.
基金Supported by the National Natural Science Foundation of China under Grant, Nos 60571060 and 10703004.
文摘Phase comparison method can enhance the measurement resolution to 10^-13/T in time domain. This method can also be used in distance measurement in the navigation and positioning. We propose a super high-resolution distance measurement based on linear phase comparison method. A high resolution scheme is put forward on the basis of the research of major factors concerning the phase comparison in the distance measurement. Conversion of a high-linearity phase difference to voltage and high-resolution voltage meter make it possible to obtain a very high phase measurement resolution. When the purpose is to measure distance, the phase noise of frequency source used in the measurement can be reduced partly. Thus this method is favourable for high resolution distance measurement. The precision of the distance measurement can reach 0.1c ps with c being the velocity of light in vacuum.
文摘A four-finger InGaAs/InP double hetero3unction bipolar transistor is designed and fabricated successfully by using planacization technology. The emitter area of each finger is 1 × 15 um^2. The breakdown voltage is more than 7V, the maximum collector current could be more than lOOmA. The current gain cutoff frequency is as high as 155 GHz and the maximum oscillation frequency reaches 253 GHz. The heterostructure bipolar transistor can offer more than 70row class-A maximum output power at W band and the maximum power density can be as high as 1.2 W/mm.
基金Supported by the National Natural Science Foundation of China under Grant No 10501053.
文摘One iterative in Grover＇s original quantum search algorithm consists of two Hadamard-Walsh transformations, a selective amplitude inversion and a diffusion amplitude inversion. We concentrate on the relation among the probability of success of the algorithm, the phase shifts, the number of target items and the number of iterations via replacing the two amplitude inversions by phase shifts of an arbitrary φ = ψ（0 ≤, ψ≤ 27r）. Then, according to the relation we find out the optimal phase shifts when the number of iterations is given. We present a new quantum search algorithm based on the optimal phase shifts of 1.018 after 0.57π√M/N iterations. The new algorithm can obtain either a single target item or multiple target items in the search space with the probability of success at least 93.43%
