Rhombus thinking, a new creative thinking method,is the combination of divergent thinking process and convergent thinking process,in which qualitative analysis is carried out before quantitative analysis This method t...Rhombus thinking, a new creative thinking method,is the combination of divergent thinking process and convergent thinking process,in which qualitative analysis is carried out before quantitative analysis This method tries to solve the bottle neck problem in intelligent CAD based on the extension theory The rhombus thinking method to the scheme design of new products is applied In this process, firstly, the matter element expression for the know information are set up, and then a set of matter elements are opened up by matter elements extension method; Finally,the useful information are got by appraisal method of dependent degree It has been successfully applied to the scheme design for the cutter store of machining center Theoretical and experimental results demonstrated fhat the method is much more accurate,objective and efficient than the traditional展开更多
Hybrid square/rhombus-rectangular lasers(HSRRLs) consisting of a Fabry–Perot(FP) cavity and a square/rhombus microcavity(SRM) are proposed and demonstrated for realizing single-mode lasing with a wide wavelength tuni...Hybrid square/rhombus-rectangular lasers(HSRRLs) consisting of a Fabry–Perot(FP) cavity and a square/rhombus microcavity(SRM) are proposed and demonstrated for realizing single-mode lasing with a wide wavelength tuning range. The SRM is a deformed square microcavity with a vertex extended to the FP cavity to control the coupled mode field pattern in the FP cavity. Single-mode operation with a side-mode suppression ratio(SMSR) over 45.3 dB is realized, and a wide wavelength tuning range of 21 nm with SMSR >35 dB is further demonstrated by adjusting the injection currents of the SRM and the FP cavity simultaneously. Furthermore, a 3-dB modulation bandwidth of 14.1 GHz and an open-eye diagram at 35 Gb/s are demonstrated for the HSRRL.展开更多
The purpose of shipping risk early-warning is that some effective measures are taken to reduce risk probability before the risk brings heavy loss.The shipping risk has the dynamic characteristic,so the key of early-wa...The purpose of shipping risk early-warning is that some effective measures are taken to reduce risk probability before the risk brings heavy loss.The shipping risk has the dynamic characteristic,so the key of early-warning is to choice risk early-warning index correctly and evaluate risk grade quantitatively.According to the element extension theory,the rhombus inference model is applied to establish the index system.And the problem of risk grade evaluation can be solved by the assessment model of multi-index performance parameter,which is developed by the extension engineering method.Finally,the main shipping risks and their grades are identified by the example analysis based on the statistical data,which shows the effective and feasible of the shipping risk early-warning method.展开更多
In supersonic wind tunnels, the airflow at the exit of a convergent-divergent nozzle is affected by the connection between the nozzle and test section, because the connection is a source of disturbance for supersonic ...In supersonic wind tunnels, the airflow at the exit of a convergent-divergent nozzle is affected by the connection between the nozzle and test section, because the connection is a source of disturbance for supersonic flow and the source of disturbance generated by this disturbance propagates downstream. In order to avoid the disturbance, the test can only be carried out in the rhombus area. However, for the supersonic nozzle, the rhombus region is small, limiting the size and attitude angle of the test model. An integrated supersonic nozzle is a nozzle and a test section as a whole, which is designed to weaken or eliminate the disturbance. The inviscid contour of the supersonic nozzle is based on the method of characteristics. A new curve is formed by the smooth connection between the inviscid contour and test section, and the boundary layer is corrected for the overall curve. Integrated supersonic nozzles with Mach number 1.5 and 2 are designed, which are based on this method. The flow field is validated by numerical and experimental results. The results of the study highlight the importance of the connection about the nozzle outlet and test section. They clearly show that the wave system does not exist at the exit of the supersonic nozzle, and the flow field is uniform throughout the test section.展开更多
The magnetic impacts upon the transport of heat and mass of an electrically conducting nanofluid within an annulus among an inner rhombus with convex and outer cavity with periodic temperature/concentration profiles o...The magnetic impacts upon the transport of heat and mass of an electrically conducting nanofluid within an annulus among an inner rhombus with convex and outer cavity with periodic temperature/concentration profiles on its left wall are assessed by the ISPH method.The right wall has Tcand C,cflat walls are adiabatic,and the temperature and concentration of the left wall are altered sinusoidally with time.The features of the heat and mass transfer and fluid flow through an annulus are assessed across a wide scale of Hartmann number Ha,Soret number Sr,oscillation amplitude A,Dufour number Du,nanoparticles parameterΦ,oscillation frequency f,Rayleigh number Ra,and radius of a superellipse a at Lewis number Le=20,magnetic field’s angle g=45°,Prandtl number Pr=6.2,a superellipse coefficient n=3/2,and buoyancy parameter N=1.The results reveal that the velocity’s maximum reduces by 70.93%as Ha boosts from 0 to 50,and by 66.24%as coefficient a boosts from 0.1 to 0.4.Whilst the velocity’s maximum augments by 83.04%as Sr increases from 0.6 to 2 plus a decrease in Du from 1 to0.03.The oscillation amplitude A,and frequency f are significantly affecting the nanofluid speed,and heat and mass transfer inside an annulus.Increasing the parameters A and f is augmenting the values of mean Nusselt number-(Sh)and mean Sherwood number^-(Nu).Increasing the radius of a superellipse a enhances the values of^(Nu)and^(Sh).展开更多
文摘Rhombus thinking, a new creative thinking method,is the combination of divergent thinking process and convergent thinking process,in which qualitative analysis is carried out before quantitative analysis This method tries to solve the bottle neck problem in intelligent CAD based on the extension theory The rhombus thinking method to the scheme design of new products is applied In this process, firstly, the matter element expression for the know information are set up, and then a set of matter elements are opened up by matter elements extension method; Finally,the useful information are got by appraisal method of dependent degree It has been successfully applied to the scheme design for the cutter store of machining center Theoretical and experimental results demonstrated fhat the method is much more accurate,objective and efficient than the traditional
基金National Natural Science Foundation of China(NSFC)(11704375,61527823,61875188)
文摘Hybrid square/rhombus-rectangular lasers(HSRRLs) consisting of a Fabry–Perot(FP) cavity and a square/rhombus microcavity(SRM) are proposed and demonstrated for realizing single-mode lasing with a wide wavelength tuning range. The SRM is a deformed square microcavity with a vertex extended to the FP cavity to control the coupled mode field pattern in the FP cavity. Single-mode operation with a side-mode suppression ratio(SMSR) over 45.3 dB is realized, and a wide wavelength tuning range of 21 nm with SMSR >35 dB is further demonstrated by adjusting the injection currents of the SRM and the FP cavity simultaneously. Furthermore, a 3-dB modulation bandwidth of 14.1 GHz and an open-eye diagram at 35 Gb/s are demonstrated for the HSRRL.
基金the Natural Science Foundation of Tianjin (No.07JCYBJC13100)
文摘The purpose of shipping risk early-warning is that some effective measures are taken to reduce risk probability before the risk brings heavy loss.The shipping risk has the dynamic characteristic,so the key of early-warning is to choice risk early-warning index correctly and evaluate risk grade quantitatively.According to the element extension theory,the rhombus inference model is applied to establish the index system.And the problem of risk grade evaluation can be solved by the assessment model of multi-index performance parameter,which is developed by the extension engineering method.Finally,the main shipping risks and their grades are identified by the example analysis based on the statistical data,which shows the effective and feasible of the shipping risk early-warning method.
基金supported by Supersonic Laboratory of CAAANational Nature Science Foundation of China (Nos.11672283, 11872349)
文摘In supersonic wind tunnels, the airflow at the exit of a convergent-divergent nozzle is affected by the connection between the nozzle and test section, because the connection is a source of disturbance for supersonic flow and the source of disturbance generated by this disturbance propagates downstream. In order to avoid the disturbance, the test can only be carried out in the rhombus area. However, for the supersonic nozzle, the rhombus region is small, limiting the size and attitude angle of the test model. An integrated supersonic nozzle is a nozzle and a test section as a whole, which is designed to weaken or eliminate the disturbance. The inviscid contour of the supersonic nozzle is based on the method of characteristics. A new curve is formed by the smooth connection between the inviscid contour and test section, and the boundary layer is corrected for the overall curve. Integrated supersonic nozzles with Mach number 1.5 and 2 are designed, which are based on this method. The flow field is validated by numerical and experimental results. The results of the study highlight the importance of the connection about the nozzle outlet and test section. They clearly show that the wave system does not exist at the exit of the supersonic nozzle, and the flow field is uniform throughout the test section.
基金the Deanship of Scientific Research at King Khalid University,Abha,Saudi Arabia,for funding this work through the Research Group Project under Grant Number(RGP.2/144/42)funded by the Deanship of Scientific Research at Princess Nourah Bint Abdulrahman University through the Fast-track Research Funding Program。
文摘The magnetic impacts upon the transport of heat and mass of an electrically conducting nanofluid within an annulus among an inner rhombus with convex and outer cavity with periodic temperature/concentration profiles on its left wall are assessed by the ISPH method.The right wall has Tcand C,cflat walls are adiabatic,and the temperature and concentration of the left wall are altered sinusoidally with time.The features of the heat and mass transfer and fluid flow through an annulus are assessed across a wide scale of Hartmann number Ha,Soret number Sr,oscillation amplitude A,Dufour number Du,nanoparticles parameterΦ,oscillation frequency f,Rayleigh number Ra,and radius of a superellipse a at Lewis number Le=20,magnetic field’s angle g=45°,Prandtl number Pr=6.2,a superellipse coefficient n=3/2,and buoyancy parameter N=1.The results reveal that the velocity’s maximum reduces by 70.93%as Ha boosts from 0 to 50,and by 66.24%as coefficient a boosts from 0.1 to 0.4.Whilst the velocity’s maximum augments by 83.04%as Sr increases from 0.6 to 2 plus a decrease in Du from 1 to0.03.The oscillation amplitude A,and frequency f are significantly affecting the nanofluid speed,and heat and mass transfer inside an annulus.Increasing the parameters A and f is augmenting the values of mean Nusselt number-(Sh)and mean Sherwood number^-(Nu).Increasing the radius of a superellipse a enhances the values of^(Nu)and^(Sh).