排序方式： 共有92条查询结果，搜索用时 15 毫秒
1.
作为我国中小企业特别是高新技术企业的融资平台,创业板在自主创新国家战略和构建多层次资本市场体系中起着举足轻重的作用。通过对355家创业板上市公司的创新投入及其影响因素进行分析,结果表明公司的创新水平与净利润、资产总额、董事学历有完全的正相关关系,与资产负债率、控股股东持股比例和董事会规模之间没有显著关系。 相似文献
2.
针对实验室GEM实时成像平板探测器多通道实时数据采集的需要,设计了一套基于FPGA和网络接口芯片的数据采集系统.该系统具有精度高、速度快、通道多、通用性强、安全可靠的特点,具有较高的应用价值. 相似文献
3.
孟艳琼 《武汉理工大学学报》2002,24(4):126-128,135
从我国目前的现实环境出发，理性地分析了我国现阶段推出创业所面临的问题，并有针对性地提出了一些对策和建议。 相似文献
4.
O. Bouianov M. Bouianov R. Orava P. Semenov V. Tikhonov 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2000,450(2-3):277-287
The charge induction mechanism and signal formation on the electrodes of the Gas Electron Multiplier (GEM) detector are discussed in detail. The method of simulating the effective gas gain, transparency and charge losses in GEM structures is developed. Results on simulation of various GEM geometries are consistent with published experimental data. 相似文献
5.
金属陶瓷物理性能与材料组分和空间组织结构密切相关,其组成相的形态分布具有分形特征。基于渗流理论和分形理论,通过对材料微观结构图像的二值化处理进行导通相分形维数计算,建立分形维数与导通相微观形貌、渗流临界指数之间的定量表征,研究Mo-ZrO2金属陶瓷全组分范围内材料微观结构与电导率和热导率之间的关系。结果表明：导通相面积分形维数随着Mo体积分数的增加而增加,电导率与分形维数遵循渗流转变特征。采用通用有效介质(GEM)方程建立基于导通相分形维数的金属陶瓷电导率和热导率模型,实现材料微观组织定量分析结果与金属陶瓷的渗流模型相结合,有效预测材料宏观物理性质的梯度变化。 相似文献
6.
S. Procureur S. AuneJ. Ball Y. BedferM. Boyer H. Colas A. GiganonP. Konczykowski F. KunneC. Lahonde-Hamdoun N. MakkeC. Marchand O. MeunierA. Morreale B. MorenoH. Moutarde D. NeyretS. Platchkov F. Sabatié 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,659(1):91-97
A detailed study of several Micromegas detectors prototyped for the COMPASS and CLAS12 experiments is presented. Using a 150 GeV/c pion beam, the discharge probability was measured for several detector variants including bulk and non-bulk Micromegas. A detector equipped with an additional GEM foil as pre-amplification stage was also tested. A resistive coating of the readout strips was found to reduce the amplitude of the discharge by at least two orders of magnitude which was below the detection limit of the experimental setup. The effects of the micro-mesh type and material were investigated as well as the influence of the drift gap. Response in the presence of a 1.5 T transverse magnetic field was also studied. The measurements presented were performed during a RD51 beam test period. 相似文献
7.
A. Orthen H. Wagner H. J. Besch R. H. Menk A. H. Walenta U. Werthenbach 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2003,500(1-3):163-177
A Micro compteur à Trous (MicroCAT) structure which is used for avalanche charge multiplication in gas filled radiation detectors has been optimised with respect to maximum electron transparency and minimum ion feedback. We report on the charge transfer behaviour and the achievable gas gain of this device. A three-dimensional electron and ion transfer simulation is compared to results derived from electric current measurements. Similarly, we present studies of the charge transfer behaviour of a Gas Electron Multiplier (GEM) by current measurements and simulations. Finally, we investigate the combination of the MicroCAT and the GEM by measurements with respect to the performance at different voltage settings, gas mixtures and gas pressures. 相似文献
8.
本文专门介绍由DVB标准化组织制订的GEM标准,内容包括GEM的由来和特点、标准的体系架构和组成部分、市场推广和应用情况以及标准未来的发展趋势等。 相似文献
9.
为了更好地评价创业板市场上市公司综合业绩,帮助投资者做出正确的选择,减少投资风险,运用SPSS软件对创业板市场首批上市的28家公司的相关数据进行因子分析,在众多的财务指标中找出几个公共因子,计算因子得分,从而得出28家创业板市场上市公司综合业绩因子得分及排序,进而对28家创业板市场上市公司综合业绩因子分析结果进行评价。 相似文献
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