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RHOMBUS THINKING METHOD AND ITS APPLICATION IN SCHEME DESIGN 被引量:3
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作者 Zhao Yanwei Wang Wanliang Science Research Center,Zhejiang University of Technology Zhang Guoxian Shanghai University 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2001年第2期156-159,共4页
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... 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 one 展开更多
关键词 Extension theory rhombus thinking method Scheme design Artificial Intelligence
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Widely tunable single-mode lasers based on a hybrid square/rhombus-rectangular microcavity 被引量:5
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作者 You-Zeng Hao Fu-Li Wang +4 位作者 Min Tang Hai-Zhong Weng Yue-De Yang Jin-Long Xiao Yong-Zhen Huang 《Photonics Research》 SCIE EI CSCD 2019年第5期543-548,共6页
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
关键词 HYBRID square/rhombus-rectangular lasers(HSRRLs) Fabry-Perot(FP) square/rhombus microcavity(SRM)
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Two dimensional coupled oscillators array with rhombus structure and its application in active antenna array 被引量:3
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作者 ZHAI LongJun JIANG YongHua LIU LongHe 《Science in China(Series F)》 2008年第12期2074-2086,共13页
Beam scanning and forming can be achieved by coupled oscillators array without phase shifter. Active antenna array based on coupled oscillators array has the virtue of low cost, high integration, and high efficiency. ... Beam scanning and forming can be achieved by coupled oscillators array without phase shifter. Active antenna array based on coupled oscillators array has the virtue of low cost, high integration, and high efficiency. Traditional two dimensional coupled oscillators array has been arranged on rectangular lattices, and phase difference of adjacent elements is limited to [-90°, 90°]. Therefore, the beam scanning range is limited to [-30°, 30°] from normal for half wavelength element spacing. A new two dimensional coupled oscillators array with rhombus structure is presented. Phase control method and phase error of the array are also provided. Stability of the array is analyzed, and stable condition is given. When this coupled oscillators array with rhombus structure is used in active antenna array, theoretical results show that phase difference of adjacent elements reach the limit of [-180°, 180°] along the horizontal and vertical directions. Therefore, it has wider beam scanning range than that of a rectangular lattice structure. 展开更多
关键词 coupled oscillators array rhombus structure active antenna array STABILITY phase control
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Self-organizing Map Method Based on Real Rough Sets Space and Its Application of Pattern Recognition 被引量:2
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作者 肖迪 胡寿松 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2006年第1期72-76,共5页
This paper presents a real rough sets space and corresponding concepts of real lower and upper approximation sets which correspond to the real-valued attributes. Therefore, the real rough sets space can be investigate... This paper presents a real rough sets space and corresponding concepts of real lower and upper approximation sets which correspond to the real-valued attributes. Therefore, the real rough sets space can be investigated directly. A rhombus neighborhood for SOM is proposed, and the combination of SOM and rough sets theory is explored. According to the distance between the weight of winner node and the input vector in the real rough sets space, new weight learning rules are defined. The modified method makes the classification of the output of SOM clearer and the intervals of different classes larger. Finally, an example based on fault identification of an aircraft actuator is presented, The result of the simulation shows that this method is right and effective. 展开更多
关键词 rough sets theory self-organlzlng map real value rough set rhombus neighborhood pattern recognition
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一个复杂边值问题的解
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作者 李庆武 李易 《郑州大学学报(理学版)》 CAS 1987年第2期58-65,共8页
一引言随着微波理论和技术的迅速发展,对新型传输线的研究提出了更高的要求。一系列新型的微波转换过渡部件、微波滤波器和新型定向耦合器的研究,是建立在对新型传输线的理论分析基础之上的。因此,分析菱形外导体—椭园内导体传输线(以... 一引言随着微波理论和技术的迅速发展,对新型传输线的研究提出了更高的要求。一系列新型的微波转换过渡部件、微波滤波器和新型定向耦合器的研究,是建立在对新型传输线的理论分析基础之上的。因此,分析菱形外导体—椭园内导体传输线(以下简称外菱—内椭传输线)具有一定的理论意义和实用意义。这种传输线具有极化面固定、功率容量较大等优点。由于其截面复杂,因而无精确解,至今未见专文论述。本文采用“特征点图形逼近法”(具体方法见下文),导出特性阻抗和分布电容的计算公式,并由此推出在特定条件下的另外五种传输线的特性阻抗计算公式。所得结果均用初等函数表示,并附有部分计算结果,以供参考。 展开更多
关键词 rhombus outer conducterellipse inner conducter tronsmission line conformal mapping
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Research on the Method of Shipping Risk Early-Warning Based on Matter-Element Theory 被引量:4
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作者 张宇 汪波 谭振东 《Journal of Shanghai Jiaotong university(Science)》 EI 2011年第2期252-256,共5页
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
关键词 shipping risk early-warning method rhombus inference model matter-element theory
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Integrated supersonic wind tunnel nozzle 被引量:2
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作者 Junmou SHEN Jingang DONG +4 位作者 Ruiqu LI Jiang ZHANG Xing CHEN Yongming QIN Handong MA 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第11期2422-2432,共11页
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
关键词 Boundary layer DISTURBANCE Flow field Integrated supersonic nozzle Supersonic wind tunnels The rhombus region
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Double-induced-mode integrated triboelectric nanogenerator based on spring steel to maximize space utilization 被引量:2
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作者 Guanlin Liu Hengyu Guo +3 位作者 Lin Chen Xue Wang Dapeng Wei Chenguo Hu 《Nano Research》 SCIE EI CAS CSCD 2016年第11期3355-3363,共9页
Integrated multilayered triboelectric nanogenerators (TENGs) are an efficient approach to solve the insufficient energy problem caused by a single-layered TENG for achieving high output power density. However, most ... Integrated multilayered triboelectric nanogenerators (TENGs) are an efficient approach to solve the insufficient energy problem caused by a single-layered TENG for achieving high output power density. However, most integrated multilayered TENGs have a relatively large volume. Here, a double-induced-mode integrated triboelectric nanogenerator (DI-TENG) based on spring steel plates is presented as a cost-effective, simple, and high-performance device for ambient vibration energy harvesting. The unique stackable rhombus structure, in which spring steel plates act both as skeletons and as electrodes, can enhance the output performance and maximize space utilization. The DI-TENG with five repeated units in a volume of 12 cm × 5 cm × 0.4 cm can generate a short-circuit current of 51 μA and can transfer charges of 1.25 μC in a half period. The contrast experiment is conducted systematically and the results have proved that the DI-TENG has a great advantage over the single-induced-mode TENG (SI-TENG) with only one side of a friction layer on its electrode. Besides, the DI-TENG can easily power a commercial calculator and can be used as a door switch sensor. 展开更多
关键词 triboelectric nanogenerator double-induced-mode spring steelstackable rhombus structure
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Magnetic impact on heat and mass transfer utilizing nonofluid in an annulus between a superellipse obstacle and a cavity with periodic side-wall temperature and concentration
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作者 Abdelraheem M Aly Noura Alsedais 《Communications in Theoretical Physics》 SCIE CAS CSCD 2021年第11期1-17,共17页
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
关键词 Dufour number ISPH method NANOFLUID Soret number rhombus magnetic field
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Magnetic order driven by orbital ordering in the semiconducting KFe1.5Se2
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作者 Qing Jiang Dao-Xin Yao 《Frontiers of physics》 SCIE CSCD 2016年第2期75-81,共7页
The two-orbital Hubbard model is studied numerically by using the Hartree-Fock approximation in both real space and momentum space, and the ground-state properties of the alkali metal iron selenide semiconducting KFel... The two-orbital Hubbard model is studied numerically by using the Hartree-Fock approximation in both real space and momentum space, and the ground-state properties of the alkali metal iron selenide semiconducting KFel.5Se2 are investigated. A rhombus-type Fe vacancy order with stripe- type antiferromagnetic (AFM) order is found, as was observed in neutron scattering experiments [J. Zhao, et al., Phys. Rev. Lett. 109, 267003 (2012)]. Hopping parameters are obtained by fitting the experimentally observed stripe AFM phase in real space. These hopping parameters are then used to study the ground-state properties of the semiconductor in momentum space. It is found to be a strongly correlated system with a large on-site Coulomb repulsion U, similar to the AFM Mort insulator -- the parent compound of copper oxide superconductors. We also find that the electronic occupation numbers and magnetizations in the dxz and dyz orbitals become different simultaneously when U 〉 Uc (~3.4 eV), indicating orbital ordering. These results imply that the rotational symmetry between the two orbitals is broken by orbital ordering and thus drives the strong anisotropy of the magnetic coupling that has been observed by experiments and that the stripe-type AFM order in this compound may be caused by orbital ordering together with the observed large anisotropy. 展开更多
关键词 iron-based superconductor twoporbital model stripe AFM phase rhombus Fe vacancy order orbital ordering
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