To study the properties of a new surface-type infrared decoy,the numerical dispersion model and the infrared radiance model of the plates are established. In addition,the temperature of a single plate was measured dur...To study the properties of a new surface-type infrared decoy,the numerical dispersion model and the infrared radiance model of the plates are established. In addition,the temperature of a single plate was measured during combustion experiment,and the spatial position and infrared radiance of each plate are calculated in plate cloud by the two models respectively. Furthermore,the radar images of the plate cloud are simulated and analyzed in dependence of time and direction for single and multiple launching. The result shows that the surface-type infrared decoy can be a point source of interference when the missile is remote tracking. In the meanwhile,the plates cloud shelters the infrared characteristics of the plume and jets of aircraft when the missile is on IR imaging guidance mode. Moreover,With the analysis of the plate cloud dispersion at different intervals and the infrared radiation intensity in the case of different launching number,it can be concluded that a comfortable launching interval can maintain a continuous plate cloud,launching the decoys simultaneously increase the increment of the radiation intensity obviously,the multiple launching is an effective way to enhance the interference property of the decoy.展开更多
This study presents the fabrication and characterization of novel surface-type capacitive humidity sensors using vanadyl phthalocyanine（VOPc） as the active material.The devices,which comprise three different thickne...This study presents the fabrication and characterization of novel surface-type capacitive humidity sensors using vanadyl phthalocyanine（VOPc） as the active material.The devices,which comprise three different thicknesses, have been fabricated using the thermal evaporation technique.A thin film of VOPc is deposited on thoroughly cleaned glass substrates with pre-patterned Ag electrodes.The capacitive effect of the samples under humidity has been investigated. Comparison of the samples with different thicknesses shows that the thinnest device seems more sensitive towards humidity.The humidity dependent capacitance properties of the sensor make it beneficial for use in commercial hygrometers.展开更多
Au/cellulose-PEPC/Au surface-type humidity sensors were fabricated by drop-casting cellulose and poly-N-epoxypropylcarbazole （PEPC） blend thin films. A blend of 2wt% of each cellulose and PEPC in benzol was used for...Au/cellulose-PEPC/Au surface-type humidity sensors were fabricated by drop-casting cellulose and poly-N-epoxypropylcarbazole （PEPC） blend thin films. A blend of 2wt% of each cellulose and PEPC in benzol was used for the deposition of humidity sensing films. Blend films were deposited on glass substrates with preliminary deposited surface-type gold electrodes. Films of different thicknesses of cellulose and PEPC composite were deposited by drop-casting technique. A change in electrical resistance and capacitance of the fabricated devices was observed by increasing the relative humidity in the range of 0-95% RH. It was observed that the capacitances of the sensors increase, while their resistances decrease with increasing the relative humidity. The sensors were connected to op-amp square wave oscillators. It was observed that with increasing the relative humidity, the oscillator＇s frequencies were also increased in the range of 4.2-12.0 kHz for 65μm thick film sample, 4.1-9.0 kHz for 88μm thick film sample, and 4.2-9.0 kHz for 210μm sample. Effects of film thickness on the oscillator＇s frequency with respect to humidity were also investigated. This polymer humidity sensor controlled oscillator can be used for short-range and long-range remote systems at environmental monitoring and assessment of the humidity level.展开更多
To calculate the diffusion law of chaff cloud launched by aircraft,taking rectangular chaff as an example,the diffusion model of chaff cloud is established in this paper.Firstly,the coordinate systems of chaff are def...To calculate the diffusion law of chaff cloud launched by aircraft,taking rectangular chaff as an example,the diffusion model of chaff cloud is established in this paper.Firstly,the coordinate systems of chaff are defined and the motion model of chaff is established.The motion model mainly includes chaff motion equation and rotation equation,which are obtained by combining the aerodynamic moment and aerodynamic damping.Then,the influence of multi-chaff aerodynamic interference on the movement of chaff is analyzed.Finally,considering the influence of overlap area between chaffs and chaff spacing on the aerodynamic coefficients,the multi-chaff motion model is obtained,and the simulation results are compared with the test results to verify the credibility of the model.展开更多
文摘To study the properties of a new surface-type infrared decoy,the numerical dispersion model and the infrared radiance model of the plates are established. In addition,the temperature of a single plate was measured during combustion experiment,and the spatial position and infrared radiance of each plate are calculated in plate cloud by the two models respectively. Furthermore,the radar images of the plate cloud are simulated and analyzed in dependence of time and direction for single and multiple launching. The result shows that the surface-type infrared decoy can be a point source of interference when the missile is remote tracking. In the meanwhile,the plates cloud shelters the infrared characteristics of the plume and jets of aircraft when the missile is on IR imaging guidance mode. Moreover,With the analysis of the plate cloud dispersion at different intervals and the infrared radiation intensity in the case of different launching number,it can be concluded that a comfortable launching interval can maintain a continuous plate cloud,launching the decoys simultaneously increase the increment of the radiation intensity obviously,the multiple launching is an effective way to enhance the interference property of the decoy.
文摘This study presents the fabrication and characterization of novel surface-type capacitive humidity sensors using vanadyl phthalocyanine（VOPc） as the active material.The devices,which comprise three different thicknesses, have been fabricated using the thermal evaporation technique.A thin film of VOPc is deposited on thoroughly cleaned glass substrates with pre-patterned Ag electrodes.The capacitive effect of the samples under humidity has been investigated. Comparison of the samples with different thicknesses shows that the thinnest device seems more sensitive towards humidity.The humidity dependent capacitance properties of the sensor make it beneficial for use in commercial hygrometers.
基金GIK Institute of Engineering Sciences and Technology for the support extended to this work
文摘Au/cellulose-PEPC/Au surface-type humidity sensors were fabricated by drop-casting cellulose and poly-N-epoxypropylcarbazole （PEPC） blend thin films. A blend of 2wt% of each cellulose and PEPC in benzol was used for the deposition of humidity sensing films. Blend films were deposited on glass substrates with preliminary deposited surface-type gold electrodes. Films of different thicknesses of cellulose and PEPC composite were deposited by drop-casting technique. A change in electrical resistance and capacitance of the fabricated devices was observed by increasing the relative humidity in the range of 0-95% RH. It was observed that the capacitances of the sensors increase, while their resistances decrease with increasing the relative humidity. The sensors were connected to op-amp square wave oscillators. It was observed that with increasing the relative humidity, the oscillator＇s frequencies were also increased in the range of 4.2-12.0 kHz for 65μm thick film sample, 4.1-9.0 kHz for 88μm thick film sample, and 4.2-9.0 kHz for 210μm sample. Effects of film thickness on the oscillator＇s frequency with respect to humidity were also investigated. This polymer humidity sensor controlled oscillator can be used for short-range and long-range remote systems at environmental monitoring and assessment of the humidity level.
基金This work is supported by the National Natural Science Foundation of China(grant number 61471390).
文摘To calculate the diffusion law of chaff cloud launched by aircraft,taking rectangular chaff as an example,the diffusion model of chaff cloud is established in this paper.Firstly,the coordinate systems of chaff are defined and the motion model of chaff is established.The motion model mainly includes chaff motion equation and rotation equation,which are obtained by combining the aerodynamic moment and aerodynamic damping.Then,the influence of multi-chaff aerodynamic interference on the movement of chaff is analyzed.Finally,considering the influence of overlap area between chaffs and chaff spacing on the aerodynamic coefficients,the multi-chaff motion model is obtained,and the simulation results are compared with the test results to verify the credibility of the model.
