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21.
This paper describes a global optimization design of quasi-optics power combiner of solid-state millimeterwave resonator. It is operated in the frequency range from 50 to 300 GHz using GaAs Gunn diodes. It is shown that sourcearrays containing N2 (N=3,5,...2K+1, where k is positive integer) individual elements. It is very efficient power transfer of energy from the source-array to the fractional power of the fundamental beam mode etc.. The RF output power exceeded the sum of the individual diodes to be threefold to sevenfold. And this data is the global optimization solution.  相似文献   
22.
人力资源的预测方法   总被引:1,自引:0,他引:1  
人力资源规划是必不可少的管理环节.科学的人力资源规划,必须建立在对人员供、需的准确预测的基础上.本文讨论人力资源预测的问题和转移矩阵等方法的使用.  相似文献   
23.
本文的研究目的是探讨激光冠内漂白治疗死髓牙变色的治疗作用。材料与方法 :漂白基本操作同激光活髓牙变色的漂白操作程序。先将牙龈及口唇有效防护 ,将漂白药物放在唇舌两面并同时封入根冠内。结果 :所有牙齿的灰暗变色均有 3- 5级的色度提高。平均治疗次数为 3.4± 0 .75 ,脱色 85 %以上的占 89%。结论 :牙齿创伤和牙髓分解是冠内变色的常见原因 ,激光冠内漂白是治疗这种变色的有效手段 ,可以完全恢复患者的自信。  相似文献   
24.
本文主要介绍了硅中硼离子注入校准样品的制备与研究。分别用三台SIMS仪器对样品进行了深度剖析与比对,并对用作校准目的的样品主要参数进行了定值。  相似文献   
25.
All-optical wavelength conversion of 10-Gb/s signal based on four-wave mixing is experimentally demonstrated in a 30-m-long dispersion-flattened microstructure fiber with small positive dispersion. For an average pump power of 26 dBm, the conversion efficiency was around -19.5 dB with the fluctuation less than ±1.4 dB, covering a conversion bandwidth of 20 nm. The eye diagram of the converted signal shows good eye opening.  相似文献   
26.
Radiation of an electric dipole located along an arbitrary direction in the presence of a chiral slab is formulated using matrix analysis in conjunction with Fourier transform techniques. Moreover, dyadic Green's function of such a structure may be determined for further investigation porpose.  相似文献   
27.
Xue  De-Sheng  Li  Fa-Shen 《Hyperfine Interactions》2004,156(1-4):31-40
Hyperfine Interactions - Nanowires of metal, alloy, compound, and ferrite have been electrodeposited in anodic aluminium oxide templates. The structure and magnetic properties of the nanowires are...  相似文献   
28.
We present a simple way to synthesize FePt and ZnO (wide-band-gap semiconductor) nanoparticle composites. The FePt nanoparticles were fabricated using the method reported by Sun et al. By controlling the heating rate, 3 nm FePt nanoparticles were synthesized. Well-dispersed FePt and ZnO nanoparticle composites were prepared by further adding zinc acetate and oleyl amine into the 3 nm FePt nanoparticle dispersion. By controlling the molar ratio of the FePt and zinc acetate, FePt and ZnO nanoparticle composites with different FePt particle fractions were obtained. The intensity of photo luminescence spectra of the nanoparticle composites increases very much with decreasing FePt particle fraction, whereas the peak position shifts a little. After annealing at 550 °C for half an hour, the nanoparticle composites become magnetically hard or semi-hard with coercivity much dependent on the FePt particle volume fraction. The coercivity of the composites increases with annealing temperature. The composites hold the promise of applications in new generation recording and/or optical devices.  相似文献   
29.
Device degradation behaviors of typical-sized n-type metal-induced laterally crystallized polycrystalline silicon thin-film transistors were investigated in detail under two kinds of dc bias stresses: hot-carrier (HC) stress and self-heating (SH) stress. Under HC stress, device degradation is the consequence of HC induced defect generation locally at the drain side. Under a unified model that postulates, the establishment of a potential barrier at the drain side due to carrier transport near trap states, device degradation behavior such as asymmetric on current recovery and threshold voltage degradation can be understood. Under SH stress, a general degradation in subthreshold characteristic was observed. Device degradation is the consequence of deep state generation along the entire channel. Device degradation behaviors were compared in low Vd-stress and in high Vd-stress condition. Defect generation distribution along the channel appears to be different in two cases. In both cases of SH degradation, asymmetric on current recovery was observed. This observation, when in low Vd-stress condition, is tentatively explained by dehydrogenation (hydrogenation) effect at the drain (source) side during stress  相似文献   
30.
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