Author believe that industrial clusters can strengthen industrially competitive power of a region and promote long - run growth of the regional economy for it can gain the advantage of economics of scale and scope economy , lower transaction cost of enterprises , possess learning effect and polarization effect , benefit innovation , adapt to the variation of market demand , favour to construct regional brand and implement region marketing 本文认为,由于产业集群能获得规模经济和范围经济的好处、降低企业的交易费用、具有学习效应和极化效应、有利于创新、能够适应市场需求的变化、有利于创立区域品牌和实施区域营销,因而能有效促进区域产业竞争力的提高和区域经济的长期增长。
The result shows are as following , first , using a . c . impedance measurement to measure the compression sensibility of cfrc can eliminate the polarization effect at the electrode of cfrc specimen and the thermoelectric force of the electrode effectively ; the thermo sensitive effect can be avoided by using little electric current , so the a . c 结果表明:采用交流阻抗法测试cfrc试块的压敏效应可以有效地消除cfrc试块的电极处的极化效应和电极界面的热电动势;采用小电流供电可避免温敏效应,因此交流阻抗法要比直流电阻法稳定性好。
By the analysis of the mechanism of charge carries transporting in the detector and the polarization effect of msm detector , we get : the polarization effect of cdse detectors is mainly caused by the poor transporting of charge carries ; to avoid the polarzation effect and improve the charge carries transporting property , the detector must has a suitable anode , so as to make a more suitable electrical field 此外,本文还通过分析探测器中的电荷输运机理,对具有msm结构的探测器的极化现象进行了定性的分析,指出光生载流子输运受阻是引起极化现象的原因之一,只有改变探测器的正极接触,从而改变探测器内的电场分布,改善载流子的输运特性,才能消除极化现象。
The main works are listed as follows : ( 1 ) based on the excitation of bi - directional current pulse technique , a new measuring circuit for weak variation of resistance was proposed for electrical resistance tomography . traditional ac current source is n ' t adopted as the exciting source . through fast bi - directional current switching , the polarization effects are eliminated 该电路主要优点如下:该电路没有采用传统的交流电流激励法作为系统的设计原理,而是通过快速的正负极性电流切换来削弱直流电流激励时激励电极的极化效应,使通过直流法来测量气液两相流的电阻微弱变化成为可能。
1 . the principles of mgti interleaver is analyzed . through discussing the relation of its output spectra characters and design parameters , we get successfully the best design parameters and rectangle interleaved spectra ; thinking over practical requirement of wdm system , the design parameters of 50ghz interleaver and their errors are presented carefully ; according to the spectral function of f - p interferometer with multi - mirror , we discuss the spectra character of g - t resonator , and analyze the dispersion of mgti interleaver ; the effect of the polarization effect of splitter on isolation of mgti interleaver is analyzed experimentally and theoretically . 2 1 、分析了mgti型interleaver滤波器的基本原理,讨论了输出光谱参数和设计参数之间的关系,获得了实现矩形化光谱的最佳设计参数;根据dwdm系统的实际要求,具体给出了信道间隔为50ghz的mgti型interleaver滤波器设计参数及其误差分析;从多镜f - p腔光谱特性出发,讨论了g - t腔的特性,进而分析了mgti型interleaver滤波器的色散特性;理论结合实验,分析了interleaver滤波器中偏振分光镜偏振效应对器件隔离度的影响。