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排序方式: 共有2126条查询结果,搜索用时 15 毫秒
1.
GSM90 0 /1 80 0固定无线公用电话桌面型话机在开发过程中遇到严重的噪音问题 ,一度成为开发工作的瓶颈。本文就这一噪音问题进行了分析与测试 ,并针对干扰源采取相应的措施 ,在产品开发中付诸应用 ,最终解决了 GSM桌面型无线公话的噪音问题 相似文献
2.
随着开关磁阻电机的调速控制系统日臻完善,因其优越性能使得在各行业得到迅速推广,但在煤矿井下的特定环境中使用该调速系统仍存在着诸多问题有待分析研究。 相似文献
3.
Kwang-Hee Lim 《Korean Journal of Chemical Engineering》2005,22(2):228-233
An experiment for five stages of a biofilter-run was performed to investigate the effect of hydrophilic ethanol and hydrophobic
toluene on the biodegradation of hydrophobic toluene and hydrophilic ethanol, respectively, when waste-air containing toluene
and ethanol was treated by a biofilter. Removal efficiencies of toluene and ethanol began to decrease when inlet load surpassed
90 g/m3/h and 100 g/m3/h consistent with maximum elimination capacities of toluene and ethanol, respectively. At the end of the biofilter-run, removal
efficiencies for toluene and ethanol were decreased and maintained at 65% and 40%, respectively. The concentration of toluene
at 1st sampling port was raised by factor of two in the 3rd stage of the biofilter run when the inlet load of ethanol co-feed
was increased by 1.5 times, while the process conditions of toluene were maintained the same as those of the 2nd stage of
biofilter-run. According to the result of Mohseni and Allen, it may be interpreted that removal efficiency of hydrophobic
toluene was affected by the presence of hydrophilic ethanol when high load of hydrophobic toluene was applied like that of
the 1st sampling port of the biofilter. However it was not the case when a low load of hydrophobic toluene was applied like
those of the 2nd, 3rd and 4th sampling ports since hydrophobicity of toluene is much less that of α-pinene. Thus, it may be
suggested that biodegradation of hydrophobic VOC was interfered by hydrophilic VOC dissolved in the biolayer and the degree
of interference was proportional to the inlet load of hydrophobic VOC as well as that of hydrophilic VOC and was inversely
proportional to the solubility of hydrophobic VOC. However, it was inferred that the existence of hydrophobic toluene from
waste-air can hardly inversely hinder the removal of hydrophilic ethanol in the biofilter when timeevolutions of hydrophilic
ethanol concentrations of this experiment were compared with those of the previous experiment of biofilter to treat waste-air
containing ethanol only. 相似文献
4.
设计了一种结构简单,抗干扰能力极强的计算机通信接口电路。该电路利用模拟开关实现了全数字二态电平(1,0)与三态电平(1,0,-1)之间的相互转换;利用模拟开关导通电阻的动态效应以及MOS晶体管开启电压Vτ的衬偏效应,提高了接收电路的抗干扰能力,提出了一种与共模干扰无关的模拟数字混合接收电路。 相似文献
5.
In the first half of the paper, various types of processing pertaining to a polygon, using the 4×4 determinant theories are explained along with a new containment test algorithm of a point in a polygon. In the latter half of the paper, a general-purpose geometric processor, the POLYGON ENGINE, is presented which can deal with various types of interference problems, such as Boolean operations in solid modelling, hidden line and surface eliminations, ray tracing and so on. It is, a successor of the TRIANGLE PROCESSOR and is also based upon the 4×4 determinant theories [4–6]. While the TRIANGLE PROCESSOR processes a triangulated polygon on a triangle-by-triangle basis, the POLYGON ENGINE can treat a polygon without triangulation. The latter is expected to be more functional, more efficient and easier to use. 相似文献
6.
7.
基于数字化二次曝光干涉的光学元件波前畸变测量 总被引:1,自引:1,他引:0
将傅立叶变换条纹分析方法与二次曝光全息干涉计量相结合,提出了数字化二次曝光干涉术,用于测量光学元件引入的波前畸变。文中给出了理论分析,模拟与光学实验结果证实提出的方法具有高精度、快速的波前测量特点,可应用于激光系统中光学元件的波前畸变在线检测。 相似文献
8.
9.
叙述了YW-1无机胶的粘接强度,耐高、低温性能,耐水、油、酸、碱性能,耐老化性能等,并介绍了这种胶在机械工业方面的应用,举例说明了这种无机粘接可完全取代机械制造业中所有的过盈配合,因而能创造巨大的经济价值。 相似文献
10.
Phase extraction, phase unwrapping and phase to height conversion are consecutive steps within the fringe projection method for reconstruction of 3D objects. The procedure of determining discontinuities on the wrapped phase, resolving them and achieving the unwrapped phase is called phase unwrapping. A software system was developed that provides the ability to create many kinds of patterns with a verity of desirable properties suitable for different demands in fringe projection systems. In our previous work, an experimental study was reported based on a multi-wavelength unwrapping approach. In the following work, we implemented a new method called binary code pattern unwrapping that is based on time analysis. A comparison of the two unwrapping approaches in terms of resolution, quality, noise, depth accuracy, and computational cost is provided. 相似文献