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51.
52.
In this paper, the chromatic dispersion and chromatic dispersion slope of two kinds of triple-clad single-mode fibers with a depressed index inner cladding named WI- and WII-type were examined. A feasible approach to calculate chromatic dispersion and higher-order dispersion was established successfully, and the influences made by the optical parameters and geometric parameters on the chromatic dispersion coefficient and its slope were analyzed in detail. The calculated results show that the optical parameter R2, which symbolizes the third cladding effect, has a strong impact on the chromatic dispersion coefficient and the chromatic dispersion slope, and the degrees of such impact are closely related to the other parameters. 相似文献
53.
一种新型桥路型HTSFCL的实验研究 总被引:2,自引:0,他引:2
在研究一种新型桥路型高温超导限流器的限流原理的基础上,研制开发了一台三相600V、故障电流峰值100A的实验室样机.本文介绍了该限流器的功率电路、控制器、低温容器和高温超导磁体等部分的结构特点和功能.在三相系统中进行了各种短路故障限流实验,结果表明该限流器有较强的限流能力和重合闸能力,说明新型高温超导限流器的研究对改善电网动态性能和提高电网电能质量有十分重要的意义. 相似文献
54.
1 Introduction Stressanalystsareofteninterestedinthederivativesofthedisplacementratherthanthedisplacementitself ,becausestrainsandhencestressesarefirst orderderivativesofdisplacement.Thederivativescanbeobtainednumericallyfromthedisplacementdatabutthep… 相似文献
55.
采用旋转锥镜技术,进行激光散斑剪切照相,测量变形物体的动态扭率和斜率,拍摄一幅散斑图可获得扭率和斜率动态变化的全过程。 相似文献
56.
Thin films based on two very different metal-organic systems are developed and some nonlinear optical applications are explored.
A family of zinc complexes which form perfectly polar assemblies in their crystalline state are found to organize as uniaxially
oriented crystallites in vapor deposited thin films on glass substrate. Optical second harmonic generation from these films
is investigated. A simple protocol is developed for thein-situ fabrication of highly monodisperse silver nanoparticles in a polymer film matrix. The methodology can be used to produce
free-standing films. Optical limiting capability of the nanoparticle-embedded polymer film is demonstrated 相似文献
57.
可变坡水槽作为研究水流及泥沙运动特性和水力学实验的一种设备已被广泛应用,本文论述了作者所研制的小型可变坡水槽的结构及其特点。 相似文献
58.
We introduce the notion of signature for relations in mapping class groups and show that the signature of a Lefschetz fibration over the 2-sphere is the sum of the signatures for basic relations contained in its monodromy. Combining explicit calculations of the signature cocycle with a technique of substituting positive relations, we give some new examples of non-holomorphic Lefschetz fibrations of genus and which violate slope bounds for non-hyperelliptic fibrations on algebraic surfaces of general type.
59.
60.
Dispersion compensating fibers (DCFs) are being widely used as dispersion compensation techniques because of its superior characteristics. This work reports the theoretical modelling of a single mode DCF having W-shaped shallow as well as deeply depressed clad profile. The DCFs have been designed and optimized by suitable adjusting different fiber parameters such as, central relative index difference (Δ+), inner core radius (a), depression depth parameter (ρ), normalized end position of the depressed clad (p), etc. at a given spot size . The figure of merit (FOM) characteristics including the bend loss as well as other losses associated with fiber manufacturing technique have been thoroughly investigated. Performances of these DCFs for recent wavelength division multiplexing (WDM) transmission system have also been discussed. By adjusting different fiber parameters, the effective core area (Aeff) of the above DCFs can be controlled to minimize the effect of non-linearities on them. 相似文献